No spark, 7 volts at coil terminal 15

[ahlem]

I have no spark. I tested coil resistance per the Bentley manual and am within spec. The + terminal #15 has only ~7 volts rather than 12.
1989 325is auto. Suggestions?

[Cephas]

Check the crankshaft position sensor. On the passenger side of the engine bay, by the crankshaft pulley. Bentley will have specs for it

[RobDog]

Check the obc code relay box. The obc relay is on the drivers side, under the kick panel and directly behind the abs module. The obc relay is a black plastic box with 2 green plugs aprox. and 4x5x1 inches. The 2 largest wires of about 8 ( green and green/red) should have 12v going through them. If only 1 wire has 12v and the other wire has low/no voltage then that's your problem. Then cut the 2 wires and splice them together to bypass the obc relay if you are having voltage issues with the obc relay

[RobDog]

Also check your main relay and make sure it is a 87, 87 and NOT an 87, 87a. This will cause no spark also.

[ahlem]

Thanks for the feedback.
The CPS is new. I will check the main relay and OBC relays this evening.
Hopefully the 87,87 and 87,87a will be self explanatory? I've had the car for 8 years and haven't changed the main relay.

[RobDog]

The pins on the 5 pin main relay are labeled on the bottom and sometimes on the side of the relay. The 2 center pins are pins 87 and 87. If they read 87 and 87a then you have the wrong relay. If you have not changed or messed with the main relay and the car ran before than that is not likely the problem, but it never hurts to check. You could have the correct relay that has gone bad after years of use.

[ahlem]

Well, I started with the main relay. I pulled it out and cleaned the spade terminals with 600 grit and put it back in. It started right up. It will be interesting to see if this is a long term fix or just something else waiting to recur,