Having some trouble with my 945. I was experiencing intermittant 'stumbling' and an occasional complete engine stop. A few minutes on the side of the road and it would run fine. The tach would drop to zero when this happened. I did a full ABS stop and the car died and will not restart.
I have replaced the RPM sensor. Checked all the fuses, sprayed every electrical connector I can find under the hood with electronic cleaner. I pulled all the relays out of the tray and inspected the PC boards and all were pristine. The relay near the ABS computer (radio supp.?) opens and closes with key on/off. Just before it died, I replaced the distributor cap and rotor and changed the oil. I have power on both sides of the coil with key on, but no flash on the neg. side when cranking. Removing the coil wire from the dist. and holding it near the engine block while cranking produces no spark.
I get a 1 1 1 signal from OBD socket 2 and further tests from the FAQ archives are suspect, because I get some codes that match and some don't. Third press of the button causes the car to go through a series of tests I didn't see in FAQ. Radiator fan, fuel injectors and various other clicking and whirring under the hood. From socket 6, I get no signal at all. I feel I have memorized the FAQ in the last week!
Sudden death from severe braking causes me to think a mechanical cause is the problem. The ground strap at the motor mount on the drivers side is in tact, but the passengers side is broken. I used some heavy wire to connect between top bolt of mount and the lower bolt. Still no start.
Can someone help my car before I start using it for target practice?
Thanks,
Mark McAllister
PS, I want my '84 240 back!

I replaced the ignition control module with the Bosch part, to no avail. I was able to buy my old 240 back yesterday, and today I have a puddle of red coming out from under it. I'm ready to buy a Kia!!
Does anyone have any other idea what could cause it to not run? Coil? The local auto parts chain 'tested' it and their readings showed intermittant 'oks'. He wanted to sell me one, but.....

In our hosue, we teach "driveway mechanics": puddle of "red" means a/t fluid. Take a look at the cooler lines for a leak.

Sounds as though the ignition power stage behind the driver's headlight has failed. This is the amplifier that provides a square wave to the coil. No signal, no ignition.

I have a 93 940T which won't start. This is the second time it has happened in a couple of months, both times after sitting for about a week without being started. Last time it finally started after numerous tries and then letting it sit. This time, no luck. Called local volvo shop, described problem (no spark, no voltage at coil, no engine codes) and they said it was the radio suppression relay (small black box on fender just aft of the battery). Replaced it. Still no start! Tell me about the ignition stage relay - is it the white cluster just above the battery on the inner fender? Any other ideas?

Thanks.

The radio suppression relay is easy to check. If it clicks when key is turned on, it's okay, but you probably know that now. Ignition stage relay (it seems to have a lot of names i.e. ignition control module, power stage, etc.) on my non turbo 940 is on the left inner fender by the airbox. A very small part with a large connector and price tag to match. Possibly the RPM sensor at the back of the engine is bad. Before you take any of this to heart, my car has had these things replaced and still wont run. When you get yours running, please share the info....

Thanks, Ring. I have the part out, rechecked all the connections, but nothing yet. Is there a way to check the part with a VOM? Expensive little thing! It'd be nice to fix the car without throwing a lot of money at it.......

I would try some junk yards. Volvo used that module from 1987 up. Just get two, keep one in the glove compartment. It works for me.