Yes, of course, so that's why I measured at idle and while cranking the engine. Idle was 12.5V, with ignition on it went down to 12V, while cranking to 10.5V and on charge it was 14V. To the best of my knowledge, these values are OK.
Technical Fiat Punto 1.2 16V mk2b (I guess) several issues
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Technical Fiat Punto 1.2 16V mk2b (I guess) several issues
Yes, of course, so that's why I measured at idle and while cranking the engine. Idle was 12.5V, with ignition on it went down to 12V, while cranking to 10.5V and on charge it was 14V. To the best of my knowledge, these values are OK.
Pardon the delay, I took the Sunday off and had all sorts of errands today.
I tried fiddling with that relay, the problem is those terminals are quite narrow and I had trouble shorting the pins. I ended up using narrow tweezers, there were some sparks, but the pump wouldn't be heard with ignition on.
I also tried inserting the relay in there and lifting it just a little bit and then shorted the pins on the relay itself, but still nothing.
OK, this is the situation. On the back of the lock I have two three pin connectors. I'll do a little diagram here.
(1) (4)
(2) (5)
(3) (6)
When I turn ignition on, there is a short between 1 and 4.
When I crank the engine, there is a short between 1 and 2 and 1 and 3. I tried shorting these pins individually, and I did it over my ampmeter. It measured some 5A on both occasions, but the starter was nowhere to be heard. At first I though I fried something, but things turned out OK.
A short recap. After fiddling with that relay, ignition started acting almost normal again. I tried turning ignition on good 15 times, started the engine a few times, it worked perfectly. Probably till tomorrow. I just can't eliminate anything, can I?
One non rhetorical question, how is this fuel pump supposed to operate? I'm assuming it pumps fuel from the tank to the injectors. Does it operate until specific pressure is obtained? Why does it turn on every time (when it does) you turn on ignition several times in the row, where does the fuel that got pumped in just moments before go? I'm assuming it has to operate during normal engine operation, is that correct?
I tried fiddling with that relay, the problem is those terminals are quite narrow and I had trouble shorting the pins. I ended up using narrow tweezers, there were some sparks, but the pump wouldn't be heard with ignition on.
I also tried inserting the relay in there and lifting it just a little bit and then shorted the pins on the relay itself, but still nothing.
OK, this is the situation. On the back of the lock I have two three pin connectors. I'll do a little diagram here.
(1) (4)
(2) (5)
(3) (6)
When I turn ignition on, there is a short between 1 and 4.
When I crank the engine, there is a short between 1 and 2 and 1 and 3. I tried shorting these pins individually, and I did it over my ampmeter. It measured some 5A on both occasions, but the starter was nowhere to be heard. At first I though I fried something, but things turned out OK.
A short recap. After fiddling with that relay, ignition started acting almost normal again. I tried turning ignition on good 15 times, started the engine a few times, it worked perfectly. Probably till tomorrow. I just can't eliminate anything, can I?
One non rhetorical question, how is this fuel pump supposed to operate? I'm assuming it pumps fuel from the tank to the injectors. Does it operate until specific pressure is obtained? Why does it turn on every time (when it does) you turn on ignition several times in the row, where does the fuel that got pumped in just moments before go? I'm assuming it has to operate during normal engine operation, is that correct?
For the ignition switch you need a wiring diagram that shows which wire goes where. I might be able to look at the Panda one, but not until Friday.
The fuel system pressure is maintained by the pump. There will be a pressure control of some sort. This might be in the pump, or on the end of the fuel rail that supplies the injectors. Different systems vary. If in the pump there is likely just to be a supply pipe to the injectors. If at the fuel rail, there will be a return pipe to allow the excess to run back to the tank.
When the engine stops, the pressure will gradually fall.
When the ignition is first turned on, the pump will run for a few seconds to pressurise the system, then stop. It stops to prevent it pumping the fuel out if there is as leak.
As the engine is cranked, the pump runs again, for as long as it is cranking.
Once the engine fires, and the key is released to the normal run position, the pump will only continue running if the engine provides either a rotational signal, (crank sensor, cam sensor, ignition distributor, depending on system), or in some cases, if engine oil pressure is ok.
If for any reason the engine stops, a stall, or a crash, that signal will be lost, or oil pressure will drop, so the pump stops. This prevents it pumping the tankful across the road if the crash has damaged the fuel lines.
Older systems mainly used oil pressure as this was a simple switch that said yes/no to the pump relay. Modern systems, the ECU receives some or all of these signals and then tells the pump yes/no, with either a feed or earth for the pump relay.
The relay will have two terminals for the switch, and two that are switched, to supply the pump. You need to ensure you are bridging the feed to the pump.
The fuel system pressure is maintained by the pump. There will be a pressure control of some sort. This might be in the pump, or on the end of the fuel rail that supplies the injectors. Different systems vary. If in the pump there is likely just to be a supply pipe to the injectors. If at the fuel rail, there will be a return pipe to allow the excess to run back to the tank.
When the engine stops, the pressure will gradually fall.
When the ignition is first turned on, the pump will run for a few seconds to pressurise the system, then stop. It stops to prevent it pumping the fuel out if there is as leak.
As the engine is cranked, the pump runs again, for as long as it is cranking.
Once the engine fires, and the key is released to the normal run position, the pump will only continue running if the engine provides either a rotational signal, (crank sensor, cam sensor, ignition distributor, depending on system), or in some cases, if engine oil pressure is ok.
If for any reason the engine stops, a stall, or a crash, that signal will be lost, or oil pressure will drop, so the pump stops. This prevents it pumping the tankful across the road if the crash has damaged the fuel lines.
Older systems mainly used oil pressure as this was a simple switch that said yes/no to the pump relay. Modern systems, the ECU receives some or all of these signals and then tells the pump yes/no, with either a feed or earth for the pump relay.
The relay will have two terminals for the switch, and two that are switched, to supply the pump. You need to ensure you are bridging the feed to the pump.
I am assuming you do not understand what you are supposed to be doing.
You will need an assistant. the pump only runs for the first 5 seconds after the ignition is switched on.
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Just a note from having a dead key myself
The fkrst few times the car will prime up - but the ecu after a few primes wont always fire up the pump, or if it does its only a split second.....
Abit of a red herring - ignore it
Id defo test that transponder reciever - that connection normally os quiet easy to pop off
Test the ohms of the ring - shouldnt be stupidly high resistance but i dont know the spec of it
Ziggy
The fkrst few times the car will prime up - but the ecu after a few primes wont always fire up the pump, or if it does its only a split second.....
Abit of a red herring - ignore it
Id defo test that transponder reciever - that connection normally os quiet easy to pop off
Test the ohms of the ring - shouldnt be stupidly high resistance but i dont know the spec of it
Ziggy
Ziggy, I have a spare key with no transponder chip. it always runs the pump.
Anyway, the pump should always run with the relay bridged even without the ignition on.
I found this http://fiat-punto-cars.info/electrical-systems/210-wiring-diagrams but I didn't find it that helpful.
Thanks for the detailed explanation, it's somewhere along the lines of what I was thinking, what left me puzzled is the fact the pump will run many consecutive times as the ignition is turned on repeatedly, leaving me under the impression that the fuel pressure is not a factor.
I believe I shorted the correct pins on the relay.
As per this schematics, the two pins on the right are feeding the pump, the two on the left are control pins. I shorted the right pins. Also, I tried repeating this operation a bit earlier with my ampmeter. I measured some 3.5A through the short connection, but the pump didn't turn on. I also measured some 12.5V on these pins.
To make things perfectly clear: I turned the ignition on, the pump didn't operate. I removed the relay and shorted the two pins. Confirmed that I did have a short connection by measuring the current through it. The pump did not operate. I did all of this on the T9 relay, which is the red relay on the left side, in the middle.
Have you seen the pictures of my car's engine area?
I'm not certain what lead you to this conclusion. I'll reiterate the issue, maybe I'm missing something.
Normal operation:
1. I turn the ignition on.
2. All dash board lights come on. Only "check engine, battery charge, check oil" remain lit up after the few initial seconds.
3. The fuel pump can be heard below the back seat for something like 5 seconds, as you stated.
Abnormal operation:
1. I turn the ignition on.
2. All dash board lights come on. A varied selection of lights remains lit up after the initial few seconds. Lately, it's mostly "battery charge" and "key coding" lights.
3. I can not hear the pump working.
4. When I try shorting the correct pins (as per above) on the T9 relay, I can not get the pump to work. I can not hear it, therefore I assume it is not working.
I'm an electrical engineer myself, even though not in this area so my experience with electronics is limited, but I fully understand how relays or pumps operate in general. This is a special case, however, as with the underlying issue there are also various signals and test conditions that need to be taken into account.
To confirm, I can not get the pump to turn on by shorting the pins on the T9 relay in the fuse box.
I'm not hoping I'll be able to repair this by myself, but I am hoping I'll manage to understand better what's going on, since I doubt any electrician in the area will be willing to devote that much time to sorting out a number of issues this vehicle is having, which may very well all stem from the same problem, but still. If I take it to any of these guys, they'll just give it minimum priority and it will sit for days on the parking lot before any time is dedicated to it.
Hi Ziggy. Maybe you have missed it, but I have the same issue with both keys. I can't see any difference between using the two.
What you state about the pump, I did experience partially. On some occasions, I would hear the pump operating for just a split second. However, just yesterday I turned the ignition on for some 15 times in just a few minutes, and the pump operated for the full duration as it usually does each and every time. For that reason I became interested about where does that fuel go.
I tried unplugging the connector on the aerial, but it may have been just stuck due to some dust buildup (further stuck thanks to rather high temperatures) and I was reluctant about forcing it. I'll go try again and will measure the resistance.
I'll try doing this as well.
OK, firstly a correction regarding the pump.
Now I tried to short the relay both with ignition on and off and in both cases the pump operates. I measure 3.5A and 12V on the relay pins and the pump operates. Earlier today there was a match on and probably a bit too much background noise so I didn't hear it working. Yesterday, however, I did the same thing and it didn't work and I did have the assistance of my brother who was sitting in the car listening for the pump.
Either way, the pump checks out.
Secondly, I measured some 35OHM on the aerial. My multimeter showed some 36OHM but these test leads appear to have some 1OHM resitance of their own. I had problems with removing the plug because it had a small latch on the lower side which needed to be pressed in, something I realized after having the entire ring removed from the lock.
Also I found opportune to test the ignition with the aerial disconnected and it behaved as erratically as before. The pump turned once or twice when turning ignition on. The "key coding" lamp was on while performing these tests. What should one expect if immobilizer was active? Everything working as usual on the dasbhoard (with added "key coding" lamp,) engine can be cranked but not started? Because, if that is so, then my car appears to be acting pretty much the same with and without the aerial. With the difference that I can "coax" the engine to start from time to time with the aerial connected.
Now I tried to short the relay both with ignition on and off and in both cases the pump operates. I measure 3.5A and 12V on the relay pins and the pump operates. Earlier today there was a match on and probably a bit too much background noise so I didn't hear it working. Yesterday, however, I did the same thing and it didn't work and I did have the assistance of my brother who was sitting in the car listening for the pump.
Either way, the pump checks out.
Secondly, I measured some 35OHM on the aerial. My multimeter showed some 36OHM but these test leads appear to have some 1OHM resitance of their own. I had problems with removing the plug because it had a small latch on the lower side which needed to be pressed in, something I realized after having the entire ring removed from the lock.
Also I found opportune to test the ignition with the aerial disconnected and it behaved as erratically as before. The pump turned once or twice when turning ignition on. The "key coding" lamp was on while performing these tests. What should one expect if immobilizer was active? Everything working as usual on the dasbhoard (with added "key coding" lamp,) engine can be cranked but not started? Because, if that is so, then my car appears to be acting pretty much the same with and without the aerial. With the difference that I can "coax" the engine to start from time to time with the aerial connected.
How can the pump circuit check out OK if yesterday you had the assistance of your brother, he was in the back, you did the same thing and it did not work?
You have a simple circuit with the relay bridged. It is completely simple for an electrical engineer to work out why the pump does not operate if it will normally operate with a bridged relay with the ignition off.
Am I missing something here??
Most likely you have a bad earth to the pump and to other items. where on my car a bundle of about ten black earths go to the front of the car as already shown.
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Assuming the pump in its circuit has only the battery, that relay and maybe some electronics on the pump itself, if closing the circuit does not start the pump one would have to assume that the battery is dead (which it isn't) or the pump is dead (which due to the intermittent nature of the issue I assume is not; assuming the pump has an impeller I guess it could get mechanically stuck periodically) or something is wrong with the electronic circuitry (if any) on the pump or the circuit is not closed.
Assuming the latter is the most probable and obvious cause, it boils down to having a loose wire or a bad contact on some of the connectors or a weak ground. In the latter case, I'm left right where I was stuck before, unable to locate the spot to which the pump is grounded.
Assuming the latter is the most probable and obvious cause, it boils down to having a loose wire or a bad contact on some of the connectors or a weak ground. In the latter case, I'm left right where I was stuck before, unable to locate the spot to which the pump is grounded.
This being the probable cause and with that ground connection looking the way it's looking on my car, how would I go around fixing the problem?
The best I can tell, this ground is affixed to a factory mounted screw which was probably welded on the inner side of that profile. There is some corrosion on this screw. Also, there is actually a second screw, just like it on the left side of the car, quite symmetrical, which is used like a mount for something, I can't recall what it was right now. This car may have had a ground box like the one on your pictures which was "lost" and the "repair guys" used the screw (to which something may have been mounted) as ground.
I'd like to have a look at an undamaged/less damaged Punto Classic.
On one of your pictures of your earths at the front of your car you can see a bundle of many black wires. I am guessing that is the same bunch of wires that goes to my earth block.
I will check on my car.
How hard can this be?
:slayer:
On my car it appears the headlight earths and the other earths for the pump etc are all going to the same location at the front of the car in that black box which is bolted to the car near the battery.
The pump and other earth wires reach the front of the car by travelling under the engine fuse box.
Two bundles of wires exit the engine fuse box at the very bottom of the fuse box plastic. One is for the radiator. The only other is a single bundle for the earths and headlight wires. So it is quite easy to work out which wires go where from the fusebox towards the front of the car.
After leaving the bottom of the fusebox, the headlight positive wires, and the earth wires all exit the main bundle in only one location where the main bundle divides into 1. earths 2. left hand headlight positives and 3 right hand headlights positives.
The headlight earths must be using the same earths as the fuel pump heater motor and so forth.
The pump and other earth wires reach the front of the car by travelling under the engine fuse box.
Two bundles of wires exit the engine fuse box at the very bottom of the fuse box plastic. One is for the radiator. The only other is a single bundle for the earths and headlight wires. So it is quite easy to work out which wires go where from the fusebox towards the front of the car.
After leaving the bottom of the fusebox, the headlight positive wires, and the earth wires all exit the main bundle in only one location where the main bundle divides into 1. earths 2. left hand headlight positives and 3 right hand headlights positives.
The headlight earths must be using the same earths as the fuel pump heater motor and so forth.
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There are no electronics for the fuel pump. When the engine is running the pump runs continuously.
On a left hand drive car, the pump earth goes to the impact switch under the glove box just under the carpet at the top. So you pull back the carpet slightly where it goes up the side of the car and reaches the glove box nearest to the outside of the car and you see it there. I think I am right saying a purple comes from the pump and a black goes from the impact switch to the earth block at the front of the car. Again from memory the pump positive is purple yellow.
Just assume you have one fault and fix the pump first. If you run a good earth wire to the impact switch you are likely to solve your other problems - at least as far as starting goes when you are not using many other devices. The pump earth is probably a ten amp cable - fairly thick. Your other devices will get an earth via the pump earth back to where they are all connected.
On a left hand drive car, the pump earth goes to the impact switch under the glove box just under the carpet at the top. So you pull back the carpet slightly where it goes up the side of the car and reaches the glove box nearest to the outside of the car and you see it there. I think I am right saying a purple comes from the pump and a black goes from the impact switch to the earth block at the front of the car. Again from memory the pump positive is purple yellow.
Just assume you have one fault and fix the pump first. If you run a good earth wire to the impact switch you are likely to solve your other problems - at least as far as starting goes when you are not using many other devices. The pump earth is probably a ten amp cable - fairly thick. Your other devices will get an earth via the pump earth back to where they are all connected.
Well, roll me in flour and find the wet spot.
Just as you stated, this it's right below the glove box, behind the carpet to the side. There's this large connector to which I see that yellow-purple wire from the pump seems to be connected. The bottom two pictures seem to show one of them sought after ground boxes. I'm not sure whether or not this is supposed to replace the one that was (previously?) located under the hood, but it's evident that this is a far better location to have a ground connection. It seems very clean.
Much to my surprise, the fricken nut was loose, I could undo it with my bare hands. The connection must have been very poor indeed. I tightened the nut and the car seemed to work OK the half a dozen of times I turned the ignition on, but I'll obviously just have to wait and see. The only constant is change.
Just as you stated, this it's right below the glove box, behind the carpet to the side. There's this large connector to which I see that yellow-purple wire from the pump seems to be connected. The bottom two pictures seem to show one of them sought after ground boxes. I'm not sure whether or not this is supposed to replace the one that was (previously?) located under the hood, but it's evident that this is a far better location to have a ground connection. It seems very clean.
Much to my surprise, the fricken nut was loose, I could undo it with my bare hands. The connection must have been very poor indeed. I tightened the nut and the car seemed to work OK the half a dozen of times I turned the ignition on, but I'll obviously just have to wait and see. The only constant is change.
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Some progress indeed!
You are not showing that fuel cut off (impact) switch, but you can see the black and purple wires for it in one of your pictures in the top right hand corner.
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Had quite a busy day today, so didn't have much time to fiddle with the car. I'll check for that switch in the morning, it must be there behind the ground box somewhere. I was just a bit too excited yesterday to look for it.
In the morning some of the lights (check engine and servo) were on, but after disconnecting the battery it appears they have turned off and haven't been coming back. All lights now work as intended, this is a situation that hasn't come to pass for a period longer that a few minutes in months now.
Engine started several times without any problems.
Another small problem showed up sometime this afternoon, my front left turn light has (I assume) blown out (just a coinkidink hopefully.) I think I noticed it immediately since the turn signal frequency has increased with this one light not working. I got a copy of that haynes manual so I'll try to figure out how to replace/check the bulb. Shouldn't be a daunting task, but there's really almost no working space behind the head light, especially the left one.
In the morning some of the lights (check engine and servo) were on, but after disconnecting the battery it appears they have turned off and haven't been coming back. All lights now work as intended, this is a situation that hasn't come to pass for a period longer that a few minutes in months now.
Engine started several times without any problems.
Another small problem showed up sometime this afternoon, my front left turn light has (I assume) blown out (just a coinkidink hopefully.) I think I noticed it immediately since the turn signal frequency has increased with this one light not working. I got a copy of that haynes manual so I'll try to figure out how to replace/check the bulb. Shouldn't be a daunting task, but there's really almost no working space behind the head light, especially the left one.
Those indicators were very difficult to change on my car. From memory position the flat handle level and then wiggle rearwards keeping it as level as you can. Take a picture of the handle before you start so you know which way to turn the handle when you replace it in the level position and then turn it slightly. They lock inwards like an old fashioned lightbulb with a bayonet fitting - so inwards into position and then twist. If you lock them the wrong way they are a total mother to move next time - but it can be done.
