Electrical Torment Please Help

Came back from a two-week trip and the van suddenly won't roll down automatic windows on either door from either switch, moonroof won't open with any switch, instrument panel has no activity from fuel gauge, tachometer, and temperature gauge. Additionally, Ive had a history of needing to press the gear stick override button to put car in gear. However, now the automatic transmission will not shift out of first gear once it's in drive. Fuses I've located seem okay.

I'm not experienced with auto electrics, but no one in my city will work on the SC. Any help is appreciated.

For the gear stick override, have you tried actually holding it down while you shift the gearstick out of PARK?  For a while mine needed to be presses once to allow you to shift.  Then I found I needed to hold the red button down with one hand while shifting with the other.  Once you are out of PARK THE OTHER GEAR CHANGES WORK NORMALLY.

I have to say I feel smug that my window winders, handbrake, curtains etc are all non electric.  Less to go wrong

Hello, or should that be howdy ‘NashvilleSuperCustom’.

I’m not going to try to diagnose your electrical gremlins over the forum but if you’ve got one issue that relates to possibly several circuits then the likely culprit might be a fuse has blown or an earth point has got dislodged. It’s unlikely that a series of switches have failed or a series of circuits have packed up.

There are two large fuse holders, but both are a bit of a pain to access. There are some fuse inside the dash, but these relate to the HVAC system not the ancillaries you mention.

Take a look at the long post in my show us yours section for some useful resources and particularly what I consider are the best electrical manuals on the web. I hope these help. They show the position of the fuses, the wiring (inc colours) and the switches / motors etc in typical wiring diagram fashion.

If a fuse has blown it’s generally also a good idea to try to understand why this is the case. Fuses are there to protect circuits and if a fuse has gone, it’s likely to let go again. For example it might be that the wiring through the door grommets has worn or cracked and failed to a short circuit that has blown the fuse. To fix that you’d need to replace the dodgy door wiring and then replace the fuse.

If it’s an earth point then the wiring diagram shows these.

I think that the absolutely best diagnosis tool is a power probe, but a simple 12V multimeter and long leads works well. A clamp meter is also very handy for working out whether a wire is live, but clamp meters are a bit more expensive. The simplest tool is just a 12V bulb and a bit of wire.

The trick is to treat each circuit as a loop and make no assumptions. It can also be useful to print out the relevant wiring diagram section(s) and trace each circuit from point to point. Don't forget the earth / neg areas, too. Many auto electrical gremlins relave to bad earth.

Final point is to say that the less you have to disassemble the better. It’s normally quite easy to test connectors without taking them apart and quite a few of the electrical components might be getting quite fragile with age, as might some of the wiring (eg where the doors open).

HTH!!

p.s.  I’ve no idea whether the transmission issue is related. I have a M/T.