Auto Gear Fault

[jdoocey]

. Yesterday whilst driving,I experienced a big jolt, 'auto Gear Fault' appeared on the instrument panel and the car went into 3rd gear and wouldn't change out of it until I restarted the car. I had this with my last picasso, which ended up with me having to scrap the car as it needed the pressure regulator valves changed and was just too expensive to repair. I have brought it back to the dealer I purchased it from (NOT a Citroen dealer), and they have said NO faults showed up, but they are changing the brake pads and that will solve the problem. Does this sound likely? Brake pads could cause Auto Gear Fault??

 

I dont want to end up with a car that is beyond repair (economicaly).

 

Thanks

[paul.h]

I can not imagine how brake pads would cause the problem but see 3rd paragraph. You would be best to get a Citroen dealer to do a diagnostic check for the fault and then go back to the car dealer but the Citroen dealer would charge for this. It is possible the car dealer does not have the right diagnostic equipment to do a proper check.

 

If they are changing the brake pads is this because they are worn out and the car should not have been sold in this condition  - you could use a torch to see how thick the pad friction material is and also if the brake discs are worn since usually by the time pads have worn out the discs have also worn to their minimum thickness.

 

However, despite above thoughts, a search shows the C4 auto box goes to 3rd gear as a default setting and in this link the problem was solved for one owner by replacing worn brake pads and discs and also the brake pedal sensor http://www.honestjohn.co.uk/forum/post/?t=90102  .So let the dealer replace the pads, try and get new discs as well, and see if the problem goes. If not, then maybe a visit to a Citroen dealer may be needed.

[jdoocey]

Thanks for that. I have contacted Citroen and waiting for them to book me in for a diagnostic scan. I can understand the car going into 'Safe Mode'...ie: 3rd gear, if the brake pads were thin, but why would 'Auto Gear Fault' show up for this, thats whats confusing me. The dealer I took it back to didn't seem to comprehend the auto gear fault bit, as it had disappeared from the instrumental panel by the time I got to them (It only stays for a few seconds), so were concentrating on it being stuck in 3rd gear. 

They changed the pads, and it drove home lovely yesterday, but thats similar to what happened with my old picasso. The fault started off occurring once a week, after a few months it was happening every journey within the 1st 2 miles or so. 

 

Thanks again. I'll see what Citroen have to say. 

[Elisio]

I need a help, I have Citroen C4 and suddenly gearbox went in 3rd gear and kept stuck. I took my car to citroen dealer and until now they did not solve. it is showing ESP/ASR fault and ask for SERVICE

[paul.h]

Welcome to the forum.

 

Possibly the following copied from above may apply in your case:

However, despite above thoughts, a search shows the C4 auto box goes to 3rd gear as a default setting and in this link the problem was solved for one owner by replacing worn brake pads and discs and also the brake pedal sensor http://www.honestjoh...m/post/?t=90102 .So let the dealer replace the pads, try and get new discs as well, and see if the problem goes. If not, then maybe a visit to a Citroen dealer may be needed.

[jdoocey]

Hi. Im pretty sure it was a brake pedal sensor that solved the problem. The dealer covered the costs as well as dealing directly with Citroen to have the repair done. I still have the car and its been fine ever since (2 years on). I'm now pretty pee'd off that this could have been the solution for my previous Picasso, however was quoted £2000 upwards for the repair so sold it as Spares Or Repairs. hmm. 

[jdoocey]

Just to clarify, mine was showing 'Automatic Gear Fault' 

[jdoocey]

Paul H, could I pick your brains on another issue? Should the gearbox oil be changed at all, and if so, how often? I've has mixed information as to whether the oil should be drained and changed at all. What are your thoughts? Thanks

[paul.h]

Auto gearbox oil changes seem to be done at highish mileages by people on here and it appears to make a difference. coastline taxis usually recommends getting a dealer to do it since a diagnostic is needed to ensure the oil is hot enough when setting the level. If the level is not right the gearbox may not work properly and there are some recent posts on here which confirm this.

[lions200404]

Going into 3rd gear is called STOPPING MODE its the auto box's way of preserving itself in 3rd hydraulic these gear boxes are quite complex they have a valve body inside which controls your gear changes these are a group of sequence valves, they also have two other valves known as the BORG WARNER VALVES (mentioned extensively on this site) these are a lock off and a pressure regulation electro valve, there are six levels of DOWNGRADED MODE and many things can cause these issues from the brake switch mentioned above to blocked filter, when I first worked on the AL4 auto box I spent a lot of unnecessary time and money trying to eliminate each individual part of the gearbox, as you say yours keeps going into third hydraulic then according to the manual then it can only be in level 5 or level 6 of downgraded mode as these levels are the only time out of the 6 that it will switch itself to 3rd gear. Below are the possible faults that it could be according to the manual.

 

- THROTTLE POTENTIOMETER INFORMATION

-ENGINE TORQUE INFORMATIONMULTIFUNCTIONS SWITCH

-SUPPLY TO ANALOUGE SENSORS

-PRESSURE MODULATING ELECTROVALVE

-MAIN PRESSURE REGULATION

-HEAT EXCHANGER OIL FLOW MODULATING ELECTROVALVE

-INPUT SPEED AND OUTPUT SPEED

-INPUT SPEED AND ENGINE SPEED

-OUTPUT SPEED AND ENGINE SPEED

-ECU NOT WORKING

-SEQUENCE ELECTRO VALVES

- SUPPLY TO SEQUENCE ELECTROVALVES

- ACCELERATOR PEDAL NOT PROGRAMMED

 

Now the question you will be asking yourself is how do you determine out of that list what the problem is ? Well the answer is always the same LEXIA diagnostics the advantage of this the gearbox has its own ECU and it will give you either a fault reading as to what the problem is or via the live parameters this will at least narrow it down to a few, the most obvious thing to me reading you symptoms is either the lock up electro valve or the pressure regulation valve these are common problems with these and are quite simple to do your self there is a lot of info on here that will guide you, Regarding the ATF change this does help but doesn't cure many issues once your limit counter reaches its limit the on board computer will tell you its time for a change and as mentioned above even this isn't straight forward and you do need LEXIA to complete this for two reasons the first being to have the gear box at the correct temperature not the gar the AUTOMATIC TRANSMISSION FLUID and the second being to set the counters back to zero this allows the auto box's ECU to let the car know its has X amount of miles before the next ATF change.  if I can be of assistance in any way I would be glad to help.

Edited August 8, 2017 by lions200404