Loss of sidelights

[adam quantrill]

Just got a strange problem on the 400SX (same wiring as a 1989 400SE).

The sidelights (front and back) and instrument lights have stopped working.

The pods still pop up on sides - so it isn't the switch.

I just checked and swapped over some of the relays, and pulled relevant fuses, but can't see anything blown.

Any ideas? Just founds a wiring diagram in an old email so I'm sorted for that... so looking at this the switch independently operates the sides on a + supply, and via a separate contact the pods via grounding. Looks like the former is the most likely culprit, then....

Edited by adam quantrill on Monday 26th October 11:42

[Jonny weggie]

Hi Adam, had a similar case where my side lights,one side only/dash lights kept blowing ever time i went for a drive in the dark.
To cut a long story short, i spent weeks trying to find it and could'nt so got an auto electric chap in, he fused the front sides, back sides and the dash to find out which area was causing the problem, it was from the dash so after cutting some wire out that was'nt needed problem solved, charged £40 and have worked ever since. Dont know whether this will help or not.
Good luck.
jonny..

[adam quantrill]

Thanks, jut been out to the car park to do battle complete with multimeter, bits of wire and cutters, wiggled the switch quite heavily about 10 times and it started working.

Must have been some corrosion inside the switch that has now cleaned off. If only all wedge problems were this simple!

[GV]

My dashlights stopped working after I disconnected the eletric aerial!! To get round the problem I located the live feed at the light switch and tried a more reliable earth connection which sorted the issue. My guess with your side lights being out would be to start with the switch, test the live feed and then check the earth connection.

Having said that - I have the same problem with my temp gauge but the process I will use will be the same when I get round to it. Good job the car doesn't get too hot....

[jmorgan]

My diagram shows the boot light on the same circuit (rear sides). Is it working?

[adam quantrill]

I suspect it wasn't. THe big clue on the series 2 cars is if the instruments and both sides all go, it's probably the switch, but if only one side goes, it's a fuse.

[Richybaby]

Hi all, I get exactly the same thing just every now and again, no sides front or back and no dash, wiggling the switch or switching lights on full and than back to sides cures it, it's the flipping SD1 switches, they're open sided so let all sorts of much and fluff in there over time, my old 280i used to suffer from it also until I took them all out and cleaned them all up, it cured all sorts of intermittent gremlins on the old 280i, Cheers, Rich.

[jmorgan]

I have had those switches apart easily in the past. Did me no good as it was the heater and the rocker bridge had melted but as mentioned, the contacts were way past a good clean. Probably why it heated up.