Smoked her

sickboy · Post by **sickboy** » 07 May 2011, 19:24

1994 940. Smoke came pouring out of dash board. Headlights will not turn off even with ignition off. Lost wipers, radio and horn.
Removed knee bolster under drivers side dash and found molten wire leading to headlight switch. Of course, other wires were damaged in the heat. Main wire toasted was from the headlight switch far right side contact. Could this wire lead to the headlight relay?
I haven't dug that deep yet. Any ideas on how to fix this?

Post by **JDS60R** » 07 May 2011, 19:34

You have an electric short. Test the light switch for any shorts and then the harness. If the headlight fuse did not blow then it is possible the harness was shorting against the body ground somewhere along the burnt section of wire. Post some pics of the damage.

sickboy · Post by **sickboy** » 07 May 2011, 21:56

Attached is the headlight switch connector. Far right wire is copper strand only. Insulation burned off all through main cable (attached).

Post by **JDS60R** » 08 May 2011, 15:32

I see damage but nothing causing the short yet. Continue to check the wiring and the switch. Include inspection under the hood in the headlight circuit.

Let us know what you found when you tested the switch. It appears power (B+)is getting to the ground side. Do the lights stay on when you pull the relay?

sickboy · Post by **sickboy** » 22 May 2011, 14:32

Fixed the problem. Removed complete harness, seperated wires burnt together, spliced in new one, repaired others if needed. It came from the radio. Two wires from the harness on the back of the radio were fried. One went to the headlight switch. Everything is working (no radio). Do you have a wiring diagram for the radio system so I can fix that? Thanks. 13 hours of labor, two dollars in parts.

Post by **JDS60R** » 22 May 2011, 15:32

https://www.matthewsvolvosite.com/downlo ... iagram.pdf

sickboy · Post by **sickboy** » 23 May 2011, 23:13

A penny got into the radio box most likely through the cassette opening and eventually landed on the rear internal connections of the multi pin harness and shorted it out.
Kids! My daughters new name is Jenny Penny.