P1676

[Jeags]

Hi all,

I keep getting a recurring code P1676 stored on my 1.1 petrol 2006 C3.

The car doesn't idle well and after replacing all ignition components I still have the same issue. I think this points to the alternator and from checking the voltage while running I can see it maintains a steady 14-14.3 volts.

I am not sure as what to check next but don't want to keep throwing parts at it without being confident what the cause is.

Any advice welcome, Cheers.

[mickthemaverick]

You may find this helpful: https://carmodnerd.com/p1676/

[PaulC5]

Have you tried a Citroen dealer for a fix, could be cheaper than you replacing parts hoping to get it right without wasting too much money ?

[ozvtr]

I think the code is erroneous. The alternator has an internal regulator and the fault signal from the alternator is just a go/no go signal. I think the engine ECU is trying to tell you something is wrong, but "what we have here is failure to communicate". If the alternator is putting out 14-14.5V then there is nothing wrong with the alternator.
How old is the battery? Please don't say "it starts the car fine". How old is the battery?
If the battery is 4 or more years old, I would seriously consider replacing it. Irrespective of whether it proves to be the problem or not.

Poor idle typically is a result of vacuum leaks. Check the vacuum line to the brake booster. Check (plug) the purge valve. Check the security of the inlet manifold.

[Jeags]

Ok will do thanks. I haven't replaced the battery but it does look fairly new. Obviously that is no where near conclusive so could replace that. Tried spraying around looking for vacuum leaks to no avail.