My '91 940 wagon {140 k} has an intermittent problem with the overdrive. The upshift arrow lights up and no O.D. When I push the button nothing happens. Then after a while, it will start working ok again . What may be the problem?
Thanks

I had this exact problem with my 940T. There is a relay in the center console that needs to be replaced. It will start working after that.

The overdrive relay is probably at fault. See the 700/900 FAQ. The relay probably has bad solder joints which will need to be re-soldered.
--
john

or the electrical connector to the od solanoid under the car...if it works in the wet, but noit when its very dry..i will bet its the connector mine was like that and not obviously problamatical till i got it in my hand and it fell off!

The problem involved the OD lockout arrow staying on. This problem is not caused by a poor electrical connection at the solenoid.
--
john

yeh your probably right JOhn, but re-reading it I think i can be read either way...

so to clarify..with my problem the OD light followed the switch (i.e. it went on and off with the switch) btu the actual operation of the OD was intermitant (and would come and go by itself sometimes leaving the light on...)

From Stephaney's post you can determine that her car has an automatic transmission since she mentions the arrow as the OD indicator.

Your car must have a manual transmission since you state the OD light is on and the OD goes in and out. The symptom your car dispayed indicates either an electrical connection problem at the OD solenoid, or an internal (hydraulic) problem.
--
john

duh..of course...silly me.....fingers operating before fully engaging brain...your right of course john...