Bsi replacment

This is the place for all your Diagnostic related questions or advice.

Moderator: RichardW

Mak
New User
Posts: 1
Joined: 20 Jun 2020, 23:12

Bsi replacment

Post by Mak »

Hello all I have a bsi issue with my c4 Picasso

No indicators on n/s of car

I need to replace a bsi and I wanted ask if anyone would know if I need to match the whole part number

User avatar
GiveMeABreak
Forum Admin Team
Posts: 21577
Joined: 15 Sep 2015, 19:38
x 2163

Re: Bsi replacment

Post by GiveMeABreak »

I assume you are aware if you change the BSI you need to change the engine ECU and the Keys / fobs as these are a matched set?

What makes you think it's the BSI?

If this is the early C4 Picasso, the front indicators are supplied by the engine fusebox. The rear indicators are supplied by the BSI. But in either case, hooking it up to Diagbox / Lexia will likely provide the fault code for the component that is causing the failure.

For the front left indicator you should be getting one of these faults: A991, B991, C991 or F991
For the rear Left, you should be getting either of faults: A4BD, B4BD, C4BD or F4BD.

Although it;s not unknown, I would find it hard to believe that boith the engine fusebox and the BSI have both gone.

However, as your problem is with one compete side - in this case the left hand side, where both indicators are not working, then I suspect it will be a problem (mechanical or electrical) with the switch module under the steering wheel (often referred to as a Comms Unit). I would think this more likely than the BSI to be honest as it is also affecting the front left.