1.6 petrol auto on an 08 plate will not start or turn over

Hi all first time poster here so please bear with me.



I have a c3 1.6 petrol auto on an 08 plate and thats about as much as i know about cars, so i had to change the battey which seem simple but since then the car will not even turn over.



The battery was brand new so nothing wrong with that i have also noticed a few odd things inside the car now so on trying to start the car there is nothing no chuck as if the stater is stuck however you do have a reply click inside the car and my mate crossed the wires on the starter and it spun so seems no problem with that.





Also i noticed the display shows fuel too low and the gauge shows no bars when i know there is at least half a tank and the eco mode keeps coming on plus the aircon display lights light orange but not wording and does not work.



I asked at CITROEN and was quoted silly money just to look at the car so really need help many thanks

Welcome to the forum TOMMIEBOY,

TOMMIEBOY wrote:i had to change the battey which seem simple but since then the car will not even turn over.

A few questions,

1. Why did you need to change the battery?


2. Who changed the battery, was it you? If so, how did you change the battery?
There is a procedure to follow when changing the battery to protect the BSI computer in the car, you may have damaged the BSI.
You could try to Reset the BSI by following these procedures
https://citroenc3owners.com/citroen-c3-t ... 3-t69.html


3. Did the car not start directly after changing the battery?


4. Have you tried putting the old battery back in?


5. If the battery change went badly, then its worth checking ALL the fuses too (including the hidden maxi fuses)
You can find links to most of the fuses in this post
https://citroenc3owners.com/citroen-c3-t ... -t150.html

Hi the battery cells dried up so if the car was not started for a day or 2 it was flat and i changed the battery but was unaware of the right way to do so ( i know now ) so i have tried the BSI reset but still the same.

Car was running before changing the battery but has not ran since, had the codes read and there are 4 BSI faults the one that sticks out is no communication with ecu

one that sticks out is no communication with ecu

This is probably because the ECU has no power, check all the fuses in the engine bay, then if they are all OK - and I mean OK when tested with a meter, then try the maxi fuses hidden under the main fuses in the engine bay.

Do you have all the codes to add to the topic?

this post will help you find the fuse boxes
https://citroenc3owners.com/citroen-c3-t ... s-t36.html

this one will help you find the maxi fuses
https://citroenc3owners.com/citroen-c3-q ... 04-10.html


Do all the other electrical items work? Like the radio, dashboard, lights etc....

Checked all the fuses and all are ok i even took the fusebox off and tried it on another c3 and that one fired up as norm.

A friend said it may be a problem with the auto box not telling the ecu that it is in N or P could that be right ?

one that sticks out is no communication with ecu

A friend said it may be a problem with the auto box not telling the ecu that it is in N or P could that be right ?

But without the ECU working the signal from the auto box has nowhere to go. I think you should get the ECU talking then you can find out a little more on why it won't start.

Checked all the fuses and all are ok i even took the fusebox off and tried it on another c3 and that one fired up as norm.

So that would be the engine bay fuse box as the one in the glovebox won't work in another car

It sounds like the BSI giving problems, check the fuses in the BSI too

Did you get all the other codes from the diagnostic socket?


Other things to check are the ignition switch is actually working.

Will get the codes in the morning, yes it was the fusebox in the engine bay that i swapped over and when you turn the ignition switch there is a relay that clicks in the fuse box

Well got the codes but can not seem to find them on the net

F015
7173
7151

Comes up with Trailer relay unit bsr ? and oil sensor not characterised

F015
7173
7151

I would try a different code reader as 7173 and 7151 are missing their 'P' 'C' 'B' or 'U' and I have never seen F015 before

It could be that the BSI is in a mess.

How did you get on checking the fuses in the BSI - the fuse box in the glove box (well hidden)?
Are you sure all the fuses in the engine bay fuse box are 100% ok, tested with a meter.
e.g. F9 10A (ECUs) and F8 25A Starter motor in the engine bay fuse box.
I know you swapped the fuses boxes between cars, were they both automatics?

Did you double check the battery is installed correctly, nice clean connections, all tight and secure.

Can you think back and look to see if you managed to knock one of the other connections near by when removing or refitting the battery.

It would be worth checking the ignition switch is doing its thing as there isn't much in the circuit for getting the engine to turn over from what I can see.
Battery feeds a fuse in the engine bay fuse box (checked), which feeds the starter switch, this completes the circuit to bring in the starter contacts to allow battery power to the starter motor windings (checked). There is probably an extra fuse in there somewhere too.

Checked all the fuses with a meter and all ok the battery is ok as if i cross the wires on the back of the starter it turns but car will still not start even with easy start engine just turns.

When you turn the key there is a clicking coming from the fuse box but thats it all the fault codes are from the BSI