Picked up the 1987 Volvo wagon dl! It wont start what so ever, I put a new battery in it and when i push the clutch in and turn the key it does absolutely nothing. The car is quiet a mess (dash pulled apart and exposed wires) previous owner had ignition replaced.After awhile he had to hit underneath where you put the key for it to start again?? Absolutely nothing works! I am thinking the computer? or some major power source. I did check the fuses and and some of them had power (fuel pump, (but you cant here running,) windshield wipers (but when i try they wont work same with turn signals) the headlights worked then i unplugged the relay for them to test the wires and plugged it back in and now the relay just clicks and nothing happens. Anything will help! Thanks in advance.

 

I think you're going to need to get your hands on the 1987-1988 240 Wiring Diagrams Greenbook (TP-31099), and go through that car system by system and sort out the wiring.

the fuel pump fuse shouldn't be powered if the engine isn't turning over, except maybe for 1 second when you first turn on the power.

at the ignition switch, one or 2 red wires into pin 30(s), are they 'hot' ? they should be always on, regardless of the key, that's the power source to LOTS of stuff (like, everything that's switched with the ignition switch).

the starter motor has nothing to do with any computers. starter output from ignition switch pin 50, blue wire goes through a connector/jumper near the transmission (used if you have an automatic.. you said clutch, so its just jumpered back to itself), then from that connector, a blue-yellow wire goes to the starter solenoid pin 50. starter motor itself is on the big heavy red wire directly from the battery.

there's two 'computers' on that car, both are VERY simple limited functions. One is the "ECU", the Fuel Injection Controller, this is just forward of the passenger front door lower hinge, behind the plastic kick panel. The other is the "ICU", or Ignition Control Unit, this is up near the right headlight, mounted on the fender.

oh. 1987 DL, that could be a 740 or a 240 ? the details of what I said above are for the 240.

 

Sorry I left out some information, its a 240 series, I believe 245 or 244? and where would I get a wiring diagram book? I will check the ignition switch and wires tomorrow and let you know what I find out. Didn't know about the second computer "ICU" I will have to look in to that as well.
Thank you
-Sam