03/04/2026
Had this little peugeot partner in last week for various engine control faults. This one had been to other places but needed a good looking at.
Found 3 fault codes for additive tank open circuit, lin bus to additive tank faulty and alternator lin bus fault.
First things first its out with the scope to analyse the lin bus signal at the alternator, which tested good, so back to the additive tank to check the signal there. All good at the tank unit too. Checked all powers and grounds to the tank unit and all good. Tried to erase the codes which left me with just additive tank open circuit. After unplugging you can see someone had butchered the plug going to it.
Dropped the tank down to check it and the whole of the front fell off exposing the control unit I side. After checking the tank all over I could see it was an aftermarket tank unit. We would only ever advise a genuine unit so that it rules out any question marks so we got a new tank ordered and luckily I keep spare plugs in stock.
Repinned the plug and fitted new housing, refilled up the additive tank, refitted all and erased all codes.
Success, all codes stayed cleared after road test and now the van can go out and be able to regenerate it's dpf as and when it needs to.
Thanks to pyramid for this one.