84 245, 400k+, non-turbo, automatic transmission.
For some reason the high pressure fuel pump is not coming on. I jumped straight to the pump and it works fine, the fuel pump fuse in the car is intact, the main fuse in the engine compartment is intact and power is getting to the relay but I'm not sure its getting out. The local parts store said it would be a special order and he wasn't sure if he could even get it. That's all covered.

What I don't understand is I've found that even though the relay is a 5 pin relay there isn't a wire going to the 87a pin, Can someone explain this to me?

The relay is the least likely suspect here. It is invulnerable to everything but water.

Most likely is the car has no ignition. Spark must be made before the ECU will activate that relay. Use a bit of starter fluid or what have you in spray flammable to make sure you have ignition before troubleshooting the fuel pump. Does the car run when you bypass the relay or just the pump? Easy bypass is to jumper fuse 5 to 7. Note, fuse 7 does nothing in this car, but it has battery on it.

Next most likely is the fuel system fuse under the hood. Not the fuse itself, but the socket for it. You might see power getting to the relay through this red wire when there is no load if you're using a small test lamp or meter and still the corrosion at the blade fuse won't allow it to run the full load of the pump. Check this easily by turning the key on and checking for power at the orange wire going to the AMM. No power? The problem is in that red wire and blade fuse holder.

Before ordering a relay replacement, make sure the ECU is trying to activate the relay. The ECU supplies a ground to the yellow/red wire going to pin 85 when it sees ignition pulses at the coil primary. No, the pin 87a is not used.

This map is actually for the '83, but the only difference is the fuse #12 got moved to fuse #13 in '84. If you're fighting a no-start, be sure to roll fuse 13 before doing anything involved.



A grenade thrown into a kitchen in France would result in Linoleum Blownapart.





--
Art Benstein near Baltimore

Hi,

On the 1984 there are two separate relays and are interchangeable in design.
One is for the fuel injectors and one for the pumps. Later models combined them into one box, that still goes faulty!

You can try switching them and if the pump runs, “while cranking”, then the other relay is bad.
You can open the fuel pump relay can and push it closed to proof your circuits out to the pumps.

I had to drive my car home once with a shoestring tied around the whole works!
That was my own desperate work around away from home.


I thinking has the 87 as an output pin to the pump.
The 86 terminal is positive side of the magnetic coil.
It is not closing the contacts to carry battery power to terminal 87 from terminal 30 battery fused circuit.
Check the fuse if you are dead there.

Terminal 85 is ground for the coil. I think the ECU closes the coil to ground only after seeing a cranking signal from the ICU and the distributor chain. Of course, I might be wrong on that direction of powering the relay coils up, on both relays.

If you can post other problems you might be having, you can get more information here.

https://www.brickboard.com/RWD/volvo/1636835/220/240/260/280/now_issue_fuel_injection.html

The wiring harness on the 1984’s +&- years can pitch you some curves if it hasn’t been addressed.

Others will chime in to help diagnose!

Phil