Hello everyone, can you help a brother out with some advice?

I have a friend with a Grande Punto Dynamic 2006.

For some time she has said that it would intermittently refuse to engage 'drive' when she first starts it. After restarting the car a few times it would allow her to change from neutral to drive.

Recently she went away for a few weeks and the car was left unused in cold weather. When she returned the battery was dead and the breakdown guys were called. The car was started, but it now totally refuses to go in to drive.

Can I get some tips on what to check?

Thank you!

Ideally we need the fault codes it bringing up. Have there been any leaks under the car? It could be as simple as being low on hydraulic fluid.

Hi, Put 'Dualogic trouble shooting guide' into the 'search' box , for some hints. There are many problems that can cause trouble with these gearboxes. They are great when they work properly, but can be terrible when they don't.

Most Easterly Pandas said:

Ideally we need the fault codes it bringing up. Have there been any leaks under the car? It could be as simple as being low on hydraulic fluid.

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I'm going to check it out on Thursday so I'll try and get any fault codes out with my ELM327.



After a bit of reading I have the following check list:

1) Does the selespeed pump prime (makes a noise?) when the drivers door is opened - does the ignition need to be on for this?

2) Check level of CS fluid on the side of the gearbox. Can the CS fluid level been checked just looking from under the car?

3) Check and clean the engine bay earth straps.

4) Get ecu fault codes (of course).

Anything else I need to add to my list?

DavyP said:

Hi, Put 'Dualogic trouble shooting guide' into the 'search' box , for some hints. There are many problems that can cause trouble with these gearboxes. They are great when they work properly, but can be terrible when they don't.

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Thanks for this - I have read the guide now. Sadly I don't have Fiat specific diag. software. However it sounds like the most common cause of what my friend describes is the pump or the accumulator.

How can I check the accumulator, though? Does it just unscrew like an oil filter and will I get lots of fluid everywhere? I don't understand why weighing it will tell me about the condition?

Thank you!

Hi, definitely sounds like a pump issue, first check would be the pump fuse and/or relay. Could also try giving the pump a gentle tap as they can get stuck!
It won't be the accumulator as this controls the pressure
I'm presuming you've checked the fluid tho?

Thanks. Can you direct me to the pump relay?

I doubt the fuse since the fault has been a creeping issue.

Why not the accumulator? I thought if it is broken then pressure might not build high enough to actuate the gears?

Actually I need to admit ignorance about what the accumulator is exactly. I Googled it and one site said it allows the rate of hydraulic pressure increese to be softened if throttle position is low, to make softer gear changes at low speed. However other things suggest it is simply a pressure vessel so the pump need not run continuously. I dont see multiple connections to the accumulator so I guess the latter is correct in this case?

Really, thanks for all the help here guys!

Hi Everyone,

I've been talking to my friend has apparently while there used to be a whirring sound when the drivers door was opened, that is not happening anymore. So, pump motor aint working! Sounds like it might be an easy fix.

Can anyone point me to a guide or describe what is involved in removing the pump motor, please?

Is it best done from the engine bay or under the car? Should I remove the whole tray with fluid container and all that, or just go for unbolting the motor and withdrawing it from the pump?

Also, where is the pump relay?

Thank you!!

The pump should have a fairly hefty cable from it, with an inline plug. I'd recommend disconnecting this first and checking the power feed to it, if its getting feed this will confirm its the pump

Good point! Is the pump supposed to run all the time the drivers door is open, or does it stop after a few seconds? Basically, will I need a helper to open the door while I probe the connector?

ssashton said:

Good point! Is the pump supposed to run all the time the drivers door is open, or does it stop after a few seconds? Basically, will I need a helper to open the door while I probe the connector?

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It should run constantly if not reaching operating pressure - I'd get someone to open to door after you've connected a tester however just to make sure

Most Easterly Pandas said:

It should run constantly if not reaching operating pressure - I'd get someone to open to door after you've connected a tester however just to make sure

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Okay I get ya!

Have you removed the pump / motor before? How is it best done?

Hi Guys,

I had a look at my friends car today.

Diagnosis seems to be a failed relay, which is located next to the battery bolted on with a little tab.

I cut all that out and the pump ran just fine, so I have ordered the bits online.

The fuse for the pump was also blown. It was a 30A fuse, is that the right value?

I suppose the pump might be worn out and drawing too much current which blew the fuse but it might just be spikes from arcing at the worn relay contacts.. who knows. The pump seemed perfectly reliable once I replaced the fuse and relay, running every time it was asked.

Ok, now you have the pump running you could still have issues!
If the accumulator is shot this will make the pump run far to much which can burn out the relay and blow the fuse.
Pump brushes could also be worn , either way you need this car on diagnostics to check the system pressure, this will show if there is an accumulator problem and/or any other issues

ssashton glad it seems to be sorted. I'd keep an eye, but if it doesn't blow anything further then like you say, it may well have just been a fault relay. They can and do occasionally fail.

Most Easterly Pandas said:

ssashton glad it seems to be sorted. I'd keep an eye, but if it doesn't blow anything further then like you say, it may well have just been a fault relay. They can and do occasionally fail.

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Hopefully it will be ok, but there is a possibility that the car still has issues!
As I said the accumulator can cause this fault, hence the reason I said this needs checking PROPERLY!
If it's put on diagnostics the system pressure can be checked and also for any other faults
It is best to give people good advice IMO

Currently I used a 40A relay from Halfords to get it going, but I have now sourced a high quality 50A one with the right size terminals.

Note: Opening the old one I noticed there was a resistor across the coil terminals which is to dissipate energy in the relay coil when the circuit is broken. So I made sure to get one a relay with a diode in it (a diode does the same job here only better, it's called a freewheeling diode). Without this element, a high voltage spike can occur from the coil and possibly damage the control electronics or even short the coil.

Anyway, inside the old relay I can see the contacts had fused closed at some point.

I plan to check the current draw of the pump and that way hopefully know if it is running healthy. The easy way to check large current draw systems is to insert a known length and thickness of wire in the loop and measure the voltage drop across it. E.g. if the wire is 22 AWG (american wire gauge) and 1 ft long, it should have a resistance about 0.016 ohms. Using Ohms Law we can calculate the current flowing through it by the voltage drop we measure across it one end to the other.

The fuse for the pump is 30 amps so I hope to see the pump drawing far less than that and I'll know it's good.

Regarding the accumulator, I suppose one way to roughly know the condition is whether the system holds pressure for long. Presumably a bad accumulator would leak the pressure and the pump will need to kick in again even without a user making gear changes. Alternatively I might let the system prime and see how many times it can shift from neutral to drive and back before the pump starts up again. I think I remember reading the system should store enough pressure for 3-4 gear shifts. What do y'all think?

Old Relay Contacts




New Relay - doesn't have plastic shroud, but never mind, specs and pins are right.

Maddogdom said:

Hopefully it will be ok, but there is a possibility that the car still has issues!
As I said the accumulator can cause this fault, hence the reason I said this needs checking PROPERLY!
If it's put on diagnostics the system pressure can be checked and also for any other faults
It is best to give people good advice IMO

Click to expand...

Diagnostics are fine if you have them, but firstly they rely on good sensors and secondly I just don't have the kit for Fiat. The car is low value and about to be sold, so nobody wants to take it to a Fiat dealer. Hence the friend with some basic mechanic super-powers was called in. Doo-do-doo! I think we can manage with a bit of logic and deduction.

I went back to fit the better quality relay and new fuse today. I also measured the pump current draw.

I used a piece of 0.57mm diameter (23AWG) solid core wire I happened to have. The convenient tables on the interwebs tell me a 30cm length should have a resistance of 0.02 ohms. When the pump was getting running it started with a voltage drop across the wire of about 0.2 volts and as it got towards maximum pressure just before shutting off it hit 0.28 volts. Call it 0.3 volts and Ohms Law tells us the pump is drawing 15 amps max. The standard fuse for the pump is 30 amps so I feel this is well within spec.

Current = Voltage/Resistance.
0.3 Volts / 0.02 Ohms = 15 Amps.

Once the system was primed I could see the fluid in the container had dropped to almost half the staring level. Fluid did not return to the container at any noticeable rate whatsoever - i.e. pressure was held in the system well. I switched from neutral to reverse and back 5 times before the pump switched on again and then it only ran for a very short time maybe 2 seconds. Given this, I'm confident the accumulator is doing its job.

Diagnosis - fooked relay and nothing else! Yay!

P.S. Selespeed fluid level bang-on between the max. and min. marks before the system is primed.

Excellent, pleased it's all sorted.
If I didn't advise the use of diagnostics i would probably be slated for not doing so[emoji849]
And yes if it's holding pressure for that amount of gear changes it should be fine hopefully