I pulled the instructions off the 700/900 faq. but let my give you the rundown first. i let my brother borrow my volvo and when he gave it back, no od. he had it for about a month and drove in-town so he didnt notice it. He said that the od light would go on and off by itself and sometimes the button on the shifter would do nothing. eventually the button started working again, the od light will go on and off and the relay clicks behind the glove box. but 4th gear apparantly has gone to a better place, and i need to bring it back. if it is the relay that is causeing this and i can permantly bypass it for now until i can get the $67 together to buy a new one. i need to at least get this thing on interstate. what is the easiest way to do this? are these instructions suggesting i pull the relay and pop the white cap off and jumper from there? or what do i need to do? by the way its a 240gl



Check fuse 12: intact, ends are clean and it fits tightly.
Check for fraying or severing of the wires to the solenoid - under the car on the left side of the transmission. Pay particular attention to the metal retaining clamp near the front end of the shift lever where the wires pass through.
Make sure the wires to the switch on the shifter head are in good order. You can remove the relay and test for continuity between terminals 1 (15 on the relay) and 4 (86 on the relay) which are the switch wire terminals.
You can test the relay and solenoid by jumpering with a spade-terminal jumper wire. Pull the relay, jumper between terminals 1 (15 on the relay, or +12V) and 3 (87 on the relay, or the solenoid). This bypasses the relay and energizes the solenoid directly. Or run +12V directly to the solenoid through a long jumper wire from the battery.
[Don Foster] All this having been noted, 90%+ of overdrive failures result from relay solder cracks. See below for instructions for relay repair.