I just picked up a 1981 245 not running. Fuel pump relay wouldn't work so I figure common buy a new one. I tried a new relay still nothing. If I open the relay and hold down the contacts everything works and car runs but wont idle. I have tested all components and everything works, but I just got a brain storm and unplugged the idle speed contol module(computer for idle) and the car will idle but still no relay activation. So, my question is does anyone have any idea why the fuel pump relay won't activate and would it make sense if the module was bad that the pump won't power and is the module bad? Mind you this is my first Volvo and I am 19 but have a bunch of mechanical history and have built other cars in the past, just never a Volvo. Any advice would be great! Also, car was parked in 2010 I have been first one since to hear it run, but both fuel pumps were replaced and fuel filter just before being parked.

 

well, I can't find the wiring diagrams for a 1981, just a 1980.

the fuel pump relay coil is controlled by some electronics in the relay, that are connected to fuse 13 (power when ignition in RUN or START), and coil pin 1 (pulses when engine is turning over from the ICU, which gets timing from the hall sensor in the distributor. said relay has a circuit so when the pulses stop, it shuts the fuel pump off. this is fairly similar to the newer LH cars I'm more familiar with, on these, you get about 1-2 seconds of fuel pump when you first turn on the ignition, then it stops until the engine is cranked over.

the timing wire from the coil pin 1 to the relay is white-red, and it goes to relay pin 31b... you might put a test light on this pin of the relay and crank the motor and see if it blinks.

 

I have tested all of them and that was the one I couldn't track and had no power at. But in the diagrams I have seen a wore is also run from the door buzzer and my buzzer doesn't work if its even there. Would that have anything to do with it?

 

only buzzer I see is wired from fuse 16 (powered when headlights are on regardless of ignition) to the door switch. I see no connections between the door buzzer and any sort of fuel injection or ignition circuit.

grey wire goes from fuse 16 middle row to buzzer pin 58. white-black wire from buzzer pin 31b to door switch (grounded when door open).

again, this is from a 1980 wiring diagram, as I'm missing 81, 82, and 83 diagrams.

 

The blue and red wire from the ignition goes to fuel pump relay and also the door buzzer from the diagram I was looking at.

 

from the ignition switch? or the ignition control unit? or what?

later cars have buzzers if you leave the key in the ignition switch and open the driver door.... those later cars automatically shut off the headlights when you shut off the engine.

 

From the ignition switch and I wasn't sure if this is suppose to have a door buzzer or not because I have found disconnected wires but can't anything missing wires.

 

well, my 1980 diagram shows that blue-red wire to the fuel pump relay pin 15 is attached to the middle row of the 3 spades immediately next to fuse 13.

fyi, the 240 fuse block... each fuse has 3 spades next to it. the rightmost/rear spade is the 'input' side of the fuse, and is connected to the left side of the actual fuse. the middle and frontmost of the spades are connected to the right side/output of fuse. some of the fuses have their inputs ganged together inside the fuse block, for instance, fuses 11-12-13 have their inputs all tied together, and are fed by a blue-yellow wire from the ignition switch to the rear/rightmost lug on fuse 12.

 

Yes I have done a lot of research and have learned that. But, straight from the ignition switch the blue and red wire split 2 ways.

 

sounds like its wired wrong. main wires from ignition switch should be black from "X" to fuse 1-2-3, blue or pink from '50' to starter solenoid, and blue-yellow from 15 to fuses 11-12-13. blue-red should be the output of fuse 13. as I said, I'm missing 1981-1983 greenbooks, but its this way on 1980 and 1984 too.

oh, and 1 or 2 thicker red wires from the positive terminal to the ignition switch pin(s) 30 which are the power input to the switch. the positive terminal is a thin black box with lots of red wires, it is in turn connected directly to the battery +

 

That is how I have it wired.

 

so when the ignition key is on, is there power at fuel pump relay pin 15 (blue-red wire)? and when you crank the car over, does relay pin 31b pulse (white-red wire)? if yes and yes, then your fuel pumps should be activated.

oh, fuel pump relay pin 31, black, should be grounded.

 

Has good ground has blue and red on ignition and never tested for a cranking pulse I will try it in the morning. I wasn't aware it was suppose to pulse on crank.

 

dont know if its the same as my 87 but i had the same problem. There was a fuse holder behind the battery that went bad over the years. Not the fuse but the holder. Kinda looks like a fuseable link. I cut mine out and twisted the wires together and it started. After that i went to autozone and got a fuseable link for $5 and put it in no problem after that. that was after i hard wired the pump to a battery with out it starting i almost went and bought both pimps till my buddy found a post about the link.

 

Thanks for the ideas! But, I think my idle control module is bad or at least the ground inside it because that is where my ground for the fuel pump relay is. So, I am going to try running a ground to the relay and see.

 

I just tested this and the red and white has constant ignition power and I tried to just run a new ground to the relay and still won't activate

 

that fuse holder by the battery is specific to LH 2.x fuel injected 240's. the OP's car is CIS-E aka KE-Jetronic.

 

that red-white wire should be connected to the white wire that goes to the ignition coil pin 1, the Ignition Control Unit (ICU) pulses this to ground to fire the spark. test light on coil pin 1 while cranking should show blinking... unless you've got no spark at all, but I thought you said it ran when you manually closed the fuel pump relay, suggesting the spark is fine ?

do you have a tachometer on your dashboard? (these were optional on many years)... if you do, does the tach work when you get the car running via jimmying the fuel pump relay? the tach is also wired to coil pin 1.

 

It does run and has good spark I tested for that before jumping the relay. Sadly there is no tach and it shows no pulsing through the relay plug for the red and white wire it shows constant ignition power.

 

just to verify things, you DO see pulsing at the coil pin 1 when cranking or its running via said relay jimmy ? asking because I want to verify your measurement method will in fact show said pulsing. if you see distinct pulsing at coil pin 1, and not at relay pin 31b, then I'd be looking for that white-red wire in the vicinity of the coil. the 1980 diagram shows it wired directly to the coil, a 1984 CIS diagram shows it going to a connector/splice midway on the white wire to coil pin 1 but doesn't show where that connector is.