HI.I have an upwards pointing arrow on the dash trouble light area.This is usually controlled by the button on the gearshift, but does not respond to the switch anymore.i tried replacing the switch with one from the dismantlers but think the problem is further down the wiring.does anyone have some ideas because this keeps the car from shifting into high gear in the automatic transmission.any ideas are appreciated.thank you

Almost certainly the overdrive relay.

Part number is 3523804. It's one of the tallest relays in your fuse box.

In a typical 940/ 940 Turbo, the method to access relay is:

Hold brake. Key on. Move lever from Park to N or D. Remove ashtray/ fusebox access cover by pulling up at bottom, in front of shift lever.

Return shift lever to Park. For the next part, you'll need a Torx screwdriver, and/or possibly a phillips head screwdriver.

Remove the cigarette lighter. Grab the cover for the lighter socket with your thumb in the lighter hole and slide the plastic piece to the right inside the coin tray. It should snap right out easily.

Behind the trim, in the upper and lower left corner, there are 2 screws. They come out at odd angles. Remove them.

The coin box pulls out toward you, and can hang on the wires of the cigarette lighter. Use a flashlight to look into your dashboard. You'll be looking at the tops of the relays, like a little plastic city in there.

The OD relay should be in the front left of the fusebox. Its tall and skinny, and with a light you can read the part number 3523804 possibly. They're usually white with black printing.

Confirm that the relay clicks or does not click, by turning on the key, and operating the OD button on the shifter. You can physically feel a little click in a functioning relay. Nothing inside here can shock you or burn you, though some relays may be warm.

The relay simply pulls straight up out of the socket. Install a new one or read the FAQ about how some people repair solder joints inside relays, if you're a do it yourself type. Observe that the serial numbers face the same way when plugging it back in.

Good luck!
--Rob

I second the motion of looking at the relay for the root of the problem. If you are not familiar with its location check here:
http://www.brickboard.com/FAQ/700-900/ElectricalCircuitsRelays.htm#RelayLocations

Good luck,
Randy

Had a similar prob with my 200, not sure if the OD relay is in the same place on the 900's, but in the 200's it is located behind the center instrument panel, more specifically where the fan control nob is. I would find it, and see if it clicks when you depress the o/d button. I would also listen to the solenoid click itself to see whether or not it is being engaged, should be on the trans center-top on the driver side. You should be able to do this with only the ignition on. Hope this helps diagnose your prob.

I started getting that a year or so ago. No more arrow if I pressed the button on the side of the shift knob. When the arrow is on, it means the transmission is prevented from shifting into overdrive, which is what you want for hauling a heavy trailer. In my case, last I checked, the arrow still worked when in Park, so I expect it's a wiring problem, but it doesn't bother me enough to dig in there and check it.
--
1992 745, >500k km

1. most likely your od relay has failed

2. possibly the wiring from the solenoid has broken

3. possibly the solenoid itself has failed.

replace the relay first