Hey guys, the overdrive on my '83 245 wagon (automatic) has stopped working properly. The indicator light on the dash does not come on and there is no 4th gear. When this first occurred, I installed a spare overdrive relay and the problem was solved, but only for a short time. I had another spare, installed it, and the same thing happened. It also only worked for a short time, making me think that an anomaly is causing the relays to fail. Any thoughts out there as to what could be causing this and how to solve my problem? Could it be caused by a faulty wire from the shifter to the solenoid? Thanks ahead for helpful input - Jim

I've dealt with this problem many times on my '83 245 and, as mentioned in another comment, it is likely a cracked solder connection in the relay. It is an easy fix. Remove the relay, pop off its top, reheat the solder connections that go to the spade connectors on the circuit board.

I will say that the last time I did this I got the overdrive light back, I could hear the relay click, but still no 4th gear. Turns out that there was some corrosion on the contacts in that same relay. So, while you have it apart, clean those contacts with some extremely fine sand paper.

Vince in Montana

The problem turned out to be a broken connection in the overdrive relay. I was thrown off by the failure in 3 separate relays, thinking something was causing them (2 were junkyard finds) to burn out. I resoldered the break several days ago and the car has been shifting perfectly since.

The indicator (arrow) light comes ON when the relay is OFF, indicating an UP-shift (to OD/4th) is "available". Normally the relay is energized at Key-On (meaning no arrow light). Start by checking Fuse 11, where OD operation starts.

If the arrow light is OFF, then the relay should be ON, calling for OD operation by sending +12V to the OD solenoid on the tranny. The on/off click of the solenoid should be audible and repeatable with Key ON and engine off.

The arrow light should switch states also, as the relay is toggled by the OD switch.

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Bruce Young, '93 940-NA (current), 240s (one V8), 140s, 122s, since '63.

Threads in archives on tracing it step-by-step.
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240 drivers / parts cars - JH, Ohio

Where did you get your spares? If they are used then they probably have the same issue as your original. It is a common problem that the solder joints on the little circuit board in the relay crack over time and result in intermittent failures. Pop the top off one of your failed relays and re-solder the joints and try it.

If you determine that the relays aren't the source of the problem, inspect the wires that run to the solenoid on the transmission. I have found that the insulation these wires crack and can cause shorts. Fix/replace any bare wires there.

The spares were junkyard finds. I suppose all 3 relays could have the same solder problem. I'll also climb under the car and inspect the wire. I may have to replace the entire length, which I've done on my '91. Will report back with my findings.

A wire or solenoid could do it.
Take ohmmeter readings of each as it could be drawing to much current from wires shorting or the solenoid shorting internally.

If you have an ammeter you want to see far less the what the relay contacts are rated for.

How did the relays fail? No click or no conduction?

Phil