Peugeot 405 ph2 brake and alternator light issue

[Atlaskrukvaxt 5]

Edit: I'm writing this before posting because I don't feel like rewriting it all but I still want to share as it might help someone else with similar problems. Before pressing post I decided to go outside and doublecheck the stop light switch and the fuse box, which I did before I started writing initially. Low and behold I saw a broken fuse that I had initially missed in the cold. Fuse number 28, 15A, was gone. The fuse responsible for "Instrument panel, digital clock, height adjustment control unit, stop lights, differential lock, ride height adjustment". I replaced it and all my problems went away. 

 

Moral of the story, check and doublecheck the fuses and such obvious things before going online. 



Hi!

I've got a -95 405 with a 2L 8v engine. It has worked fine until it got a bit colder and wetter in late september. Since then I've had electrical issues that I just can't seem to hunt down. 

 

The first issue (which I solved) was that the ABS brake system was not working and it was due to a burned out contact between the left rear light and the harness. At some point a towing hook had been added to the car and the people that did the conversion used t-tap connectors which had stripped down one wire longer and longer over time and that had caused periodic shorts to ground and as a consequence a burned connector. With the cable fixed and the connector restored the ABS brakes started working and the ABS light isn't shining any more.  I figured it out because I noticed that the ABS system would be fine until I either put the car in reverse or if i used left indicators. If I did neither of those the ABS light didn't come on. 

 

Now to the second problem which I've not managed to hunt down. The alternator light is on when the engine is running. The alternator is completely fine, it gives good voltage at all RPMs and the battery hasn't shown any signs of running low. The alternator light shines brighter when I press down the brake pedal, and when this happens the clock light goes out as well as the lights for the electrical windows. The electrical windows don't work while the brake pedal is pressed. Further more the brake lights do not come on when the brake pedal is depressed.  Both problems started roughly at the same time and all other lights work. 

The most useful thing I've found in Haynes manual is attached below but it doesn't really tell me anything since all the fuses are fine. 

 

To sum up the problem;

 

No brake lights.

Alternator light is on despite alternator working fine and shines brighter when brake is used. 

Clock light goes out when brake is used

Electrical window and their lights stop working when brake is used. 

 

Thank you for reading.

 

[SootySport 23]

Weird going ons there,  I have strange electrical faults as well.  Hope you have a multimeter to help trace faults, you won’t get far without one.   My advice is rectify each problem one at time paying attention to corroded terminals and earthing points.  
As for the alternator light,  you should have 12v. coming  out of The small ign./exciter alternator terminal when the engine is running,  that will extinguish the ignition lamp in the dash.   Check wire continuity from the The terminal to the ignition dash Light.