Volvo 940 wont start.

[Lolvo 940]

Hi I've checked across fuses with voltmeter and all healthy and the plug that goes to the ignition amplifier has volts when ignition on.
The Rev counter does not move while cranking.

[Rversteeg]

Did someone already mention the radio interference suppressor relay? This relay switches the main power to the fuel injectors and the ignition coil. Located somewhere near the battery.

[aardvarkash10]

Originally Posted by Rversteeg

Did someone already mention the radio interference suppressor relay? This relay switches the main power to the fuel injectors and the ignition coil. Located somewhere near the battery.

We've been here before!

[aardvarkash10]

Originally Posted by Lolvo 940

Hi I've checked across fuses with voltmeter and all healthy and the plug that goes to the ignition amplifier has volts when ignition on.
The Rev counter does not move while cranking.

is there 12v at the coil?

[Lolvo 940]

Already swapped rsr with known good one. Made no difference. How would you check the coil? From between the two terminals or each to earth? Will have to check again but I'm sure not.
Cheers

[Laird Scooby]

Voltmeter -ve (black) lead to earth, ignition on and check you have 12v using the voltmeter +ve (red lead) on both LT terminals on the coil.

[Lolvo 940]

Hi right, just checked with voltmeter again. I have no power to coil or injectors with ignition on or cranking.
Any suggestions welcome please.

[Laird Scooby]

Find the coil +ve terminal, should have the red/blue wire on it from memory.

Now get a length of wire long enough to reach the battery from the coil.

If you have crimp connectors, select a suitable piggyback connector and crimp one on the coil end of this piece of wire.

Bare the other end of the wire, twist the strands together and fold the resultant tail of copper wire back in line with the wire so you can stuff it into a suitable gap on the battery +ve terminal.

Connect the coil end first to the col +ve terminal - there probably won't be a spare way on it to just plug onto so disconnect one of the wires from the +ve terminal, connect the piggyback to the coil and the wire you just removed to the piggyback.

Now connect the other end of that wire to the battery +ve terminal as described.

Try starting the car.

It's a bit "Heath Robinson" but will prove the point one way or another.

If it starts, let it run for a few minutes so you can check for leaks, oil pressure light going out, charge warning light going out and so on.

Try switching off at the key - it may not turn off at the key but if you turn the key to the off position and then pull the wire out of the battery terminal where you stuffed it in that should stop the engine.

If this test proves the engine runs, it's almost certainly the radio suppression relay.

Then it's a csae of finding out whether it's the relay itself or the wiring to it or what.

[Lolvo 940]

There is a thread called.... 1998 940 no spark - any suggestions please
I don't know how or if you can link to this but at the end of this he had same issue as me on same year car and ended up swapping ecu's I think.
I will still try running a wire to coil tomorrow.
Cheers Darren

[Laird Scooby]

Originally Posted by Lolvo 940

There is a thread called.... 1998 940 no spark - any suggestions please
I don't know how or if you can link to this but at the end of this he had same issue as me on same year car and ended up swapping ecu's I think.
I will still try running a wire to coil tomorrow.
Cheers Darren

If you read the final post by bob12, it sums it up - it's very confusing whether it was the ECU, the chip in the ECU or the EZK ECU.

https://www.volvoforums.org.uk/showt...0+spark&page=4


Nobody has actually answered his query so maybe we'll never know!

If you don't have a supply to the coil, you won't have a supply to the injectors either but it sounds like you have a supply to your LH2.4 ECU as it operates the fuel pimp.

Let's hope it's simply a supply problem through the RSR rather than an ECU problem causing the similar effects.