Driving my '88 240 and it won't upshift into OD. The light comes on/off when I press the button but to no avail. 3 or 4 times during my commute (40 minutes) it would upshift into OD for no apparent reason and within a couple of seconds, shift back into 3rd. If this were my 940, I'd be resoldering a relay and checking the OD solenoid but I'm not as familiar with the 200 series. Can anyone point me in the right direction?
--
Bob Kraushaar '94 945T, '91 940T(back from retirement), '88 240, '84 242T, '94 F-150, '89 560 SL, '68 Shelby GT-500 KR

My 85 turbo with auto was doing the exact same thing. I rewired the OD and nothing worked. Then I just bought a used soleniod and it worked fine after that. Note that the ATF will pour out if you remove the solenoid. I didn't know that and I made a mess and drained the ATF. good luck

Charles 1985 245ti 134K

Thanks guys, now I have a plan.
--
Bob Kraushaar '94 945T, '91 940T(back from retirement), '88 240, '84 242T, '94 F-150, '89 560 SL, '68 Shelby GT-500 KR

Bob:

I just dealt with this on my 89 245 and the culprit appears to have been dirt/grunge in the orifices where the solenoid mounts to the trans. I had already performed the relay resolder exercise and my mechanic had previously swapped out the solenoid. My OD behaved exactly as you describe. It was intermittant for a couple months and then stopped engaging altogether. I removed the solenoid and cleaned the entire area thoroughly with Brake Cleaner. Make sure to get a can that has the long spray tube so you can snake it into the trans orifices if you do this. It worked for me.

PS: A swivel head socket wrench was useful for removing the solenoid. 12mm?

Good luck

Ed

The 240 relay is accessed by removing the glovebox and you should find it to the left of the opening.

Randy

YES check the relay
resoider as needed [very likely needed]

that fixed my wife's 88 240 auto

now my question on a 4 speed stick'
where is the 4 gear switch,
and how to get at it????
my red wire is off and hanging down, and no O/D is working
I have resoilded the relay on this one
and the dash lite comes on but
no O/D ingagement

btw the O/D box is oilly
is that from the gearbox or is the O/D box oil filled too????
what weight to use and how to refill,
both the gearbox and the O/D box?????