1990 740 GL wagon electrical problem

[e777]

Hello,

I had just replaced the fuel injectors and was attempting to start. As the battery was dead I was also using a jumper battery. As the car was turning over I noticed that the check engine light was constantly on (it usually isn't). After a few attempts at cranking, the power suddenly cut out and the whole electrical system became non-responsive--no lights, nothing.

My question: what might be likely culprits for this complete and sudden power outage? I should add the the rebuilt fuel injectors, I now believe, are not compatible. They might be part of the problem (?).

--Thanks,
Eric

1990 Volvo 740 GL automatic
260,000 miles

[billofdurham]

When you were using the jump battery was it connected up the correct way? I only ask that because I have seen experienced mechanics get it wrong.

Check the main battery leads for tightness and cleanliness. On the earth (ground) lead check where it is attached to the body. Disconnect and clean the contact points on both the lead and the body - no rust, no paint.

Check fuse #1. It covers the engine control systems. If it has blown I can't see that it would cause a total failure of the electrics but it is worth checking.

Incompatible injectors - I can't see that this would cause a total outage even if they are the wrong type.

If you can get some power to the car check for any codes that may have been recorded, using the onboard diagnostic unit.

Bill.

[e777]

Thanks, Bill. I did check all fuses and they were OK. I did have the jumper hooked up correctly. I'm betting, as you suggest, that there is a loose connection near the battery. I was concerned that I had fried the car's "brain" (although I am not even sure if this model has such a computerized brain).

Thanks again.

--Eric

[billofdurham]

They do have a "brain" but it is not as complex as modern cars. It covers ignition and fuel supply.

Bill.