405 Wiring diagram

[carlo14]

Good evening people,

Is it possible to obtain a full wiring diagram for a MkII 405 2.0 petrol auto? Or especially as it relates to the air con system. I am determined to try and fix my intermittent A/C.

VIN is VF3**************[VIN obfuscated, can be read by forum staff]

Thanks

[mickthemaverick]

Hi Carlo
Unfortunately the forum has no access to the Stellantis databases at the moment although we are hoping to restore that service. In the meantime there are members with access and hopefully one of them will see your query and help you out

[xantia_v6]

Does it have manual or automatic temperature control? I should be able to find the A/C diagrams.

[carlo14]

Hi thanks, it has the automatic climate control (with Bitron unit)

[xantia_v6]

I think that these are the applicable AC diagrams.

Component numbers etc. can be decoded from: viewtopic.php?t=80489

If you give more detail of how it is intermittent, we may be able to give some advice on what to check.

[carlo14]

Thanks ever so much for these, appreciated.

Symptoms are perverse. When you start the car the A/C often does work (75% of the time). It may then work for either 2 minutes, 10 minutes, a whole day or not at all. Usually it will just work for a couple of minutes every quarter of an hour. It might go two days working virtually perfectly, ice cold, then not work for a week. The issue seems to be that the compressor's cutting in originally but then whenever it cuts out it won't start up again.

I've replaced the compressor with a new one, it's had new drier apparently, new pressure switch. I've tried a different interior heater panel, different Bitron unit, different interior climate control sensor, different fuses & relays; nothing has made a scrap of difference. More sensible people than me would have given up long ago, however a) I am not sensible and b) I love the car and want to keep it forever and c) I can't live without A/C.

Most perverse thing of all? Tilting the electric sunroof up often seems to make it start working again, although not all the time admittedly so could be co-incidence. I'm thinking this must be electrical.

[xantia_v6]

I don't know if the A/C ECU (component 8080) can be interrogated using the Peugeot Planet tool. I expected that it could, but don't see any connection to the diagnostic socket on the diagrams above.

The ECU seems to be mounted under the dashboard in the center of the car, probably making access quite difficult.


Here is the injection wiring diagram (as it seems to be relavent).



It appears that the A/C ECU requests the compressor clutch be activated via wire 8053 (which goes to pin 34 of the engine ECU), the engine ECU then (if it is feeling cooperative) activates the compressor clutch relay via wire 1234 (engine ECU pin 23). The power feed for the compressor clutch (via the relay) seems to come from the engine ECU pin 32 (which seems a bit odd to me).

[carlo14]

Thanks ever so much