Wiring diagram for 89 740GL

Hello guys,
I have a 89 740GL.

My problem: It doesn't start unless we give jump even with a brand new
battery with full charge. It doesn't even crank, selenoid doesn't click
(engage). Sometimes, the car cranks but doesn't fire up. If any of you
have an experience with this problem, please let me know.

I also need wiring diagram to pinpoint the faulty component. Does any
of you have the wiring diagram?

PS: What is Volvo DFL , if anyone knows? (it is a computer program, i
know that much)

TIA

 

Which fuel/ignition combo does your car have? there are a couple of types
including carburettor.

All the best, Peter.

700/900/90 Register Keeper,
Volvo Owners Club (UK).

 

Dunno about DFL.

For the rest, look to see if your wiring has a separate terminal that goes
under the nut on the positive battery post. Our '85 765T has one, and if
that terminal doesn't make contact not much of anything turns on. The
terminal loves to corrode and make poor contact, so its surfaces and the
mating surfaces on the clamp have to be scraped or scoured periodically. I
have even had trouble with the engine dying in left turns because of that.

While you are there, check the 10 AWG red, orange or brown (I could never
decide) wire at the positive clamp that provides power to the ECU. Sometimes
that corrodes in two and the fuel pump becomes intermittent or quits... it
can be hard to track down. Just tug gently and make sure the wire doesn't
fall apart.

Mike

 

the car is a fuel injected one. I donot know more of that. I will check
the corroded battery cables.
PS: I'm a friend of the original message poster.

 

If you're in North America then you have LH Jettronic injection and
Bosch EZK ignition.