Cooked ECU ?

This is the Forum for all your Citroen Technical Questions, Problems or Advice.

Moderator: RichardW

Tonyash56
Posts: 4
Joined: 17 Jan 2020, 23:38
x 1

Cooked ECU ?

Post by Tonyash56 »

My 2008 1.6 16v has done somthing strange,today I plugged my sat-nav into the lighter socket, and a little smoke came off it, I unplugged it quick and was stunned by what happend next......the wipers were on intermittent constantly as were the lights with the engine running,there was no radio indicators and probably no brakelights either, anyway I drove it to my works service centre, about 2 miles,once I got there I switched it off and went to tell the story to the mechanic, he said bring it in and I'll have a quick look, except now it won't start,after waiting over 2 hours for him to come and plug it up so as to get the fault code/codes, I left it and walked home, with no fault code, and the central locking not working on the remote, I must assume that the ECU has cooked, so my question is.. where can I get one and what else needs to be changed to get it working again

User avatar
GiveMeABreak
Forum Admin Team
Posts: 21203
Joined: 15 Sep 2015, 19:38
x 2114

Re: Cooked ECU ?

Post by GiveMeABreak »

Assume nothing with these - it needs investigation. You omitted to provide us with a model - but a VIN will be needed so we can identify exactly what model and options you have as well as some clues as to the circuit involved (whether the BSI or the engine fusebox from the description of the problems).

Aftermarket car electrical accessories / devices can have unforeseen consequences, especially the charging systems on them - take cheap Chinese phone chargers and adapters - some of which have been known to overheat, smoke and cause fires.

I suspect something like this may have happened and caused some electrical problems back down the line, especially if the accessory or adaptor is either drawing too much power or is not limiting the power supplied. Start with the engine fusebox and check all the fuses for any signs of damage or carbon scarring.

Did you have an adaptor plugged in as well as your accessory or just the sat nav directly powered from the 12v socket without another adaptor?

Tonyash56
Posts: 4
Joined: 17 Jan 2020, 23:38
x 1

Re: Cooked ECU ?

Post by Tonyash56 »

Sorry it's a desire, vin number VF7**************[VIN obfuscated, can be read by forum staff] just the power lead was plugged in not attatched to the sat-nav as the fuse had blown and I had put a new fuse in and was just testing it was working.however the lighter socket still works, and so does the one in the back

User avatar
GiveMeABreak
Forum Admin Team
Posts: 21203
Joined: 15 Sep 2015, 19:38
x 2114

Re: Cooked ECU ?

Post by GiveMeABreak »

Ok, so a XSARA PICASSO FAMILY SALOON 1.6 i 16v 110 (TU5JP4) Manual gearbox 5.

The Fuse F22 in the BSI (driver side dash where all the other passenger fuses are located) controls the front and rear 12V sockets, so assuming that is fine as they are working.

You have a COMMS 2000 unit under the steering wheel that is responsible for the lighting and wiping requests, but the BSI and this module as well as the engine fusebox are all interlinked. I'm wondering whether there was some feedback from a short that has fed back along the control circuit (as apart from the earth and positive feeds tot he 12V lighter socket, there is a control wire from the BSI that controls when the socket is powered or not (part of energy supplies management). So I'm wondering if there has been some feedback up through this control wire to the BSI that has caused the other systems to have a dicky fit.

So stick with the engine fusebox and check all the fuses (not just visually).

You can try a BSI reset in case one of the ECUs has been affected:

BSI Reset / Battery Disconnect / Reconnect Procedure

But your mechanic should be able to hook up his diagnostic system and provide any fault codes. Put them up here and we might be able to assist if he hasn't ascertained what the problem is by then.

Tonyash56
Posts: 4
Joined: 17 Jan 2020, 23:38
x 1

Re: Cooked ECU ?

Post by Tonyash56 »

Turns out we were thinking too much, was just a blown fuse,number 22, I think 20 amp in the inside fuse box all good again many thanks

User avatar
GiveMeABreak
Forum Admin Team
Posts: 21203
Joined: 15 Sep 2015, 19:38
x 2114

Re: Cooked ECU ?

Post by GiveMeABreak »

Ok, I elaborated as you said the lighter socket still worked which would of meant F22 would seem to be working, unless it is 'partially blown' which won't be the first time ..... but glad you have it resolved.