Technical Starter Motor or something else

[User1]

You turn the key and you hear a click and nothing else. This only happens when engine is hot. FIAT have checked everything and no fault found. The click is the small starter solonoid which then energises the starter solonoid. Is there anything else like sensors that are also part of the circuit. If all the small solonoid does is energise the starter motor solonoid is it worth just replacing the starter motor. I also need to check if there is a heat shield in place. Fiat X290 auto. Just don't fancy getting stuck again. It starts if you leave it and come back later. I have already posted about this but limited replies. Thanks for reading.

 

[Anthony489]

Hi

I have attached the starting and recharging circuit for the X250, your van will probably not be very different. The X250 has only one solenoid which is within the starter motor. The starter is A020, and gets its main high current feed from the battery via terminal A. When you turn the ignition key H001 to start, a separate medium current flows into the starter motor via terminal C. This magnetises the solenoid (part of the starter motor, it sits to one side of the main casing). The solenoid has two jobs, one is to close the main contacts inside the starter to energise the motor, the other is to pull the starter "dog" gear into mesh with the flywheel ring gear by means of an internal pivoted lever.

The "click" you hear is likely to be the solenoid only partially moving, i.e. not enough for the main contacts to be pulled closed. This is because it isn't being supplied with enough current and/or because the internal mechanical friction is too high. When the solenoid is warm, its resistance will be a little bit higher and any friction effects could be worse, so both it's possible both effects may be contributing.


It would be worth checking that the voltage between terminal C and engine earth is near enough 12 volts when the key is turned to start. If it passes this test, the finger of suspicion points to the starter motor.


I don't know if a heat shield is standard, but if it is supposed to have one and it's missing the excess heat may have dried out any lubricant in the solenoid/dog mechanism.

 

[User1]

Thanks for your reply and diagram. Will investigate heat shield next. After that looks like a starter motor as I very much doubt you can get them apart.

 

[Communicator]

The starter on an automatic cannot be operated unless the transmission is selected to "P". This interlock may be universal, it certainly applies to our Skoda Fabia, and our Saab 9-3 which also allows starting in neutral.

I only have drawings for the x244 Ducato, but I expect later models to be similar in this respect. eLearn diagram E5050 shows the contacts of relay T20 included in the starter solenoid circuit. Relay T20 is operated when the ignition is on (coil +ve), and the transmission is selected to "P" (coil -ve). The starting "INT" contact of the ignition switch still directly controls the starter solenoid, but via relay T20 contacts. However I doubt that the inclusion of the relay contacts in the circuit will have an effect dependant upon engine temperature, but there will be additional resistance in the solenoid circuit due to the relay and additional connections.

Relay T20 is located in the engine bay fusebox, opposite to the M6 power input stud.


Many years ago I suffered a similar fault on a Talbot Express. (Warm engine, and not engaging starter after short stops, but OK when cold.) The Talbot Express did have a heat shield for the starter motor, but the motor was mounted above the turbo.


I support Anthony489's reasoning of an increase in the resistance of the solenoid when it warms up, as resistance is proportional to absolute temperature.

Cure? Difficult, my Talbot Express was easy as I added a relay which was simple to add into the wiring. In the automatic Ducato, the relay (T20) is present, but the solenoid current is still routed through the ignition switch. It would be nearly impossible to alter the internal connections of engine bay fusebox, as it consists of a series of metal plates. Perhaps checking the battery connections, and engine block earth connections may help.

I am dubious as to whether replacing the starter motor, would provide a long term solution. Are there any aftermarket alarm systems connected into the starter solenoid circuit? Such items and associated wiring will contribute to the voltage drop in the solenoid circuit.

 

[User1]

Had a look yesterday and it would be possible to take a 12v feed and introduce another relay with its own power supply. I could then use the feed from the starter solonoid to drive it as the coil would be fairly low power. Just strange that it only occurs when it is hot after a long run. Have asked for a price for starter motor so will see what the damage will be. Thanks for the input it is much appreciated.

 

[Communicator]

Hi User1,

I have recently been looking into the possibility of adding a relay into the starter circuit of my manual x244. The vacant T20 relay position in the engine bay fusebox was tempting. However when I discovered how the fusebox is constructed, I shelved the idea.

With a little thought I have a completely reversible suggestion, for your proposed relay modification. I think that it should be possible to relocate relay T20 external to the fusebox, and then extend three of the existing connections, with the starter solenoid switched supply diverted to the relay coil, and a new power feed taken from the M6 positive supply stud.


Parts required.

Micro automotive relay base with connectors, (base moulding is optional).
2 off 1/4" latching (for length not latch), male blade connectors.
1 off 3/16" male blade (this may be difficult to source).
1 off 6mm ring terminal.
1 off 30A? inline fuse. (Maxi blade recommended.)
Automotive connecting wire of suitable rating.

I am attaching a pdf version of eLearn E7050 appropriate to the x244. While probably different to your more recent vehicle, it may be helpfull as a guide. You would need to investigate as to what applies on your vehicle regarding relay T20 connections.

 

[Anthony489]

Just a thought, and please don't take this the wrong way !


When these vans left the factory they presumably worked, i.e. there is no fundamental design weakness/error.

Something has therefore happened to your van, with the result that now sometimes it doesn't work. I'd recommend firstly trying to find out what's gone wrong and fixing this fault.


I appreciate that there may be reasons why this is not possible, in which case maybe that's the time to start modifying.

 

[Communicator]

Anthony489, as far as I am concerned, your input to this forum is always appreciated, and worthy of respect.


It is many years since I had almost identical problems with my Talbot Express, to which I had added an aftermarket alarm, and a hidden key operated switch. Both of these security devices were incorporated into the starter solenoid circuit.

It was several years after installing the modifications, when the starting problem first arose.

I recall removing the bolted link between the solenoid and the motor windings. With the solenoid operated, I checked voltages at all appropriate accessible points (more in those days), and failed to find a significant single voltage drop. I concluded that the operation of the solenoid was marginal, and exacerbated by my added wiring. On that vehicle the starter was mounted on the front of the engine above the turbo. I estimated that with an engine temperature of perhaps 88C, it was possible for the starter to temperature to reach 100C, thus increasing the solenoid resistance by about 30% compared with ambient. May I politely remind you, that while magnetic flux density is proportional to current, magnetic attraction is proportional to the square of the flux density.
Subsequent to my modification, identical problems were mentioned in the technical section of the MMM magazine. It is my feeling, that such mentions represent only a small fraction of the total occurences.

That being said starter motor design has changed in the last 25 years, and so has the price.

I do agree that all appropriate electrical connections should be checked.

These include main battery connections, and the engine block earth strap, which I think may be similar to that on the x250. Another possible cause could be the ignition switch starting contact. If there is any possibility of water ingress to the engine bay fusebox it could have caused an increase in resistance in the starter solenoid connections.

There is an informative thread about the engine bay fusebox, it refers to a Fiat Stilo, but the fusebox is similar.

https://www.fiatforum.com/stilo-guides/313986-how-clean-dry-out-fuse-box-near-battery.html

 

[User1]

Managed to find an identical starter motor on EBay from a scrap vehicle. Only managed 3700 miles. Anyway all numbers the same so removed mine and fitted SH one. Started first time which was great. No heat shield as it sits behind the radiator and exhaust is on the back of the engine. Once I had a running Motorhome decided it was time to take the starter motor to bits. Nothing obvious so took the solonoid off and when you press the plunger in it squeaks. So took it down to my friendly Fiat Proffesional garage that I have been using for last ten years and asked them if it should squeak. They had not had a new one to bits so could not comment but it was enough to convince them to fit a new starter under warranty. Their comment was " If Fiat query it we will just tell them it squeaks ". So will now have a spare starter motor.

As for the wiring. I have bought a 20A push button switch. I can take a wire from the starter terminal to the switch and back to the solonoid. Just have to make sure its in P or N as starter will turn bypassing all the built in safety features. Have also added a second earth strap to the body work near the starter motor.

Thanks guys for all your replies and wiring diagrams. Only time will tell.

 

[lspill]

There have been reports of other people having the same issue on other forums (new user so can't post a link).

On my X250 there is no heat shield, but the starter isn't in a particularly warm place. It's at bottom-front of the engine. The only real heat source would be the radiators, which are right in front of it.

If the new starter works, I'd be tempted to find someone who remanufactures them and have them take a look to see what they think could be the issue.

 

[ProjectorMan]

Managed to find an identical starter motor on EBay from a scrap vehicle. Only managed 3700 miles. Anyway all numbers the same so removed mine and fitted SH one. Started first time which was great. No heat shield as it sits behind the radiator and exhaust is on the back of the engine. Once I had a running Motorhome decided it was time to take the starter motor to bits. Nothing obvious so took the solonoid off and when you press the plunger in it squeaks. So took it down to my friendly Fiat Proffesional garage that I have been using for last ten years and asked them if it should squeak. They had not had a new one to bits so could not comment but it was enough to convince them to fit a new starter under warranty. Their comment was " If Fiat query it we will just tell them it squeaks ". So will now have a spare starter motor.

As for the wiring. I have bought a 20A push button switch. I can take a wire from the starter terminal to the switch and back to the solonoid. Just have to make sure its in P or N as starter will turn bypassing all the built in safety features. Have also added a second earth strap to the body work near the starter motor.

Thanks guys for all your replies and wiring diagrams. Only time will tell.

@User1 My 2019 Ducato 9-speed auto camper van seems to have exactly the same problem. Occasional refusal to restart after a long run - just a click. Then a while later will start and run as normal. Have you had any recurrence of the problem after you replaced the starter motor?

 

[bugsymike]

In the old days if the starter clicked but didn't turn and engage to start the engine, to prove the point that it was the starter/solenoid a gentle tap with a piece of wood or back of hammer handle whilst someone held the key in start position usually did the job and engine started, to show a repair was needed.
I would say especially with an automatic be very careful safety wise!!! People have been hurt or even killed trying this trick, so use common sense!!!
Auto electricians didn't like this as some "mechanics" would belt the starter with the metal end of hammer thereby making the old starter too damaged to be repaired.
On modern pre engaged starters if the solenoid is faulty that part can be replaced with a small amount of skill and tools.
However on some designs of starter the brushes that are used to spin the motor section particularly on older Fords were positioned on the end of the motor and quickly became worn and caused similar symptoms, but were harder to repair especially if the wires were "spot welded" on rather than screwed for cheapness of manufacture.

 

[User1]

I replaced the starter motor and took the one off the vehicle back to Fiat Commercial and asked them to test it. Apparently they cannot test them so they fitted a new one. So I have a spare. Its not the starter motor as it still happens very occasionally. I took a wire from the starter motor live through a fuse to a 20A push button that I mounted under the bonnet and then a wire back to the solonoid. When it happens I pop the bonnet. SWMBO sits in the drivers seat and turns the key all the way round and I push the button. Starts first time. If you leave it for 20 minutes or so it will start. No idea what causes it but we have a way to start it. It has never happened when using Stop Start. Personally I think its a bug in the software

 

[varesecrazy]

On a primitive multi jet I had this.. It was a corroded connection on The starter

 

[camionpilot]

I had this problem with 2014 Peugeot [ ford puma engine ] refused to start just the solenoid clicking , pulled it out and it seemed very dry and difficult to turn so took it apart cleaned the armature up , lubed bearings , polished all the connections with wire wheel on a dremel , reinstalled and away it went no more trouble and i sold it a year later .

Worth a try as it has to come of regardless , all it costs is a bit of time .

 

[bugsymike]

From what has been mentioned by OP it sounds as though the fault is more likely to be a physical fault rather than software as it is trying to activate the starter so some electricity is getting to it , but with not enough power to trigger the solenoid.
Have you compared the voltage at the wire that triggers the solenoid when turning the key compared with the voltage from your modification.
Incidentally pre ECU electrics I did a similar mod and it confirmed a faulty ignition switch as on some vehicles they had a habit of burning out due to the power needed to trigger the solenoids.
When working for a Lada Dealership we had brand new Ladas (Fiat 124 under license) that I fitted new ignition switches too whilst still in the showroom!!!

 

[User1]

From what has been mentioned by OP it sounds as though the fault is more likely to be a physical fault rather than software as it is trying to activate the starter so some electricity is getting to it , but with not enough power to trigger the solenoid.
Have you compared the voltage at the wire that triggers the solenoid when turning the key compared with the voltage from your modification.
Incidentally pre ECU electrics I did a similar mod and it confirmed a faulty ignition switch as on some vehicles they had a habit of burning out due to the power needed to trigger the solenoids.
When working for a Lada Dealership we had brand new Ladas (Fiat 124 under license) that I fitted new ignition switches too whilst still in the showroom!!!

Fiat was new late 2019 its 260bhp 9 speed automatic. I will have a look at the voltages next time it happens. Last time was about 5 months ago at a National Trust Car Park. We have since driven down to Spain and back without any problems 2600 miles. I know it has never happened with the Stop / Start function so whatever it is its an illusive electrical / software gremlin. Thanks for your input.

 

[ProjectorMan]

I replaced the starter motor and took the one off the vehicle back to Fiat Commercial and asked them to test it. Apparently they cannot test them so they fitted a new one. So I have a spare. Its not the starter motor as it still happens very occasionally. I took a wire from the starter motor live through a fuse to a 20A push button that I mounted under the bonnet and then a wire back to the solonoid. When it happens I pop the bonnet. SWMBO sits in the drivers seat and turns the key all the way round and I push the button. Starts first time. If you leave it for 20 minutes or so it will start. No idea what causes it but we have a way to start it. It has never happened when using Stop Start. Personally I think its a bug in the software

Disappointing that it's still happening even though you replaced the starter. Mine's a December 2019 140bhp 9-speed auto. I've only had it happen twice now, six months apart - so the first two times I was busy eliminating the aftermarket immobiliser from the equation, which I had thought was the cause.
I'm going to use my multimeter to measure the voltage at the starter solenoid when starting so when the fault does happen again, I can check if I'm getting the same voltage to the starter still.

• It only happens when the engine is warm after a run
• It has never happened during stop/start operation
• After a wait of one to two hours, it will suddenly start perfectly normally and continue to do so for months
• I can usually hear a faint 'click' coming from the engine bay when attempting to start when the problem is happening
• There are no errors or messages shown on the dashboard or OBD reader.

 

[Cornish Ian]

I would be tempted to bypass the starter circuit from the immobiliser. Perhaps immobilise another circuit instead if you want to be safe.
Some years ago I had a similar hot start problem on a different make of car. The immobiliser dropped enough voltage to prevent enough voltage reaching the starter solenoid to always pull it in properly. Cleaning the solenoid did improve things but the permanent fix was the bypass. Apparently Toad immobilisers are known to cause this problem on some cars as the wiring they use is a little too light.

 

[Communicator]

Disappointing that it's still happening even though you replaced the starter. Mine's a December 2019 140bhp 9-speed auto. I've only had it happen twice now, six months apart - so the first two times I was busy eliminating the aftermarket immobiliser from the equation, which I had thought was the cause.
I'm going to use my multimeter to measure the voltage at the starter solenoid when starting so when the fault does happen again, I can check if I'm getting the same voltage to the starter still.

Perhaps worth running a temporary monitoring connection from the solenoid terminal?

• It only happens when the engine is warm after a run

This suggests something similar to my own experience, with the resistance of the solenoid increasing due to temperature with a warm engine. (Post #8.)

• It has never happened during stop/start operation

In stop/start operation, of which I have no experience, the solenoid must be energised by a path different to that from the ignition key. Probably a relay is used as the the stop/start output.

• After a wait of one to two hours, it will suddenly start perfectly normally and continue to do so for months

My experience was only several minutes, but still embarassing after fuelling stop etc.

• I can usually hear a faint 'click' coming from the engine bay when attempting to start when the problem is happening

As noted by @bugsymike, this indicates that there is power to the solenoid, just insufficient to operate it.

• There are no errors or messages shown on the dashboard or OBD reader.

Error messages are created by electronic processors, are there any involved other than perhaps the stop/start which could use one, but this is OK.

It would be interesting to see a diagram for the ignition key, and stop/start connections to the solenoid. Where do they connect together?

On an x244 automatic, the interlock to prevent starting when Park is not selected, is performed by the contacts, of relay T20 which are included in the solenoid circuit. The x290 will probably be similar. I am always sceptical of any rush to suspect relays, but the inclusion of thr relay incurs several more push fit connections within the engine bay fusebox, which is not unknown as a source of problems. That being said I would be more inclined to suspect the ignition switch, as mentioned by @bugsymike.

To be technical, the solenoid resistance will be proportional to absolute temperature. At constant voltage this means that solenoid current, will be inversely proportional. To compound this while the magnetic effect is proporttional to current, the physical pull of a solenoid is proportional to the square of the magnetic field strength. All that takes some digesting, so to put it more simply at 90% current, you will only 81% pull. More extremely 80% current will only result in 64% pull.