Quick question - what are the fuses in the engine bay for?

[jamescmr2]

As title...

what do the fuses in the engine bay do?

Is one for the spark plug coils by any chance?
What current rating should they be?


cheers

[MrCredit]

[jamescmr2]

Thanks for that one. most informative.

reason i asked is i was cleaning up all the electrics and fuse no.4 from above was corroded badly and the plastic melted!

after cleaning everything up i tried to restart the car and it won't run (and it did a week before!). the starter motor runs and the engine is turning but it wont fire. the fuel pump was running. I then left to pick up some spare fuses and after changing it still won't start and i can't hear the fuel pump now! did hear a clicking some where from the ECU corner of the engine bay but even that has gone now.


planning to replace the fuse holder and new fuses this week. re-check all the connections but could this cause it not to fire up?

if i can hear fuel pump run and it just won't fire i'll check for a spark next time.



cheers

[joust]

These fuses often cause what you describe.

[leeshell]

Similar symptons different reason.

Looks like my ECU is playing up and although the engine turns over no ignition;something to do with actuators controlled by the ECU

(Yellowshed is looking at it now I believe - Ta Trevor...)

[jamescmr2]

thanks Joust and Leeshell. i'll let you know when my new fuse holder arrives. £4.00 off ebay incl. delivery ha

J

[jamescmr2]

New fuse box and fuses and all is running. gonna head out now for a little blast and see if the it feels better generally, that nackered fuse system can't have been good!

cheers

[andrewr]

Anyone know where to find the fuses in the engine bay on an M400?

Thanks
Andrew

[Adrian W]

andrewr said:

Anyone know where to find the fuses in the engine bay on an M400?

Thanks
Andrew

about 3 inches above the ECU

[Rob_W]

andrewr said:

Anyone know where to find the fuses in the engine bay on an M400?

Thanks
Andrew

They are on the bulkhead near the ECU but almost impossible to see, you can maybe see the bottom of two out of the bank of four. If you feel around going forward from the AC compressor pulley you will feel them.

[andrewr]

Found them. Unfortunately they are all good.

The fuel pump is not priming.

I have reseated the 4 relays and fuses. Any ideas where to start looking?

Thanks
Andrew

[andrewr]

Checked the Relays and they all work.

Does anyone know which Relay is the fuel pump - I have 4

Also, the US manual does not show any of the fuel pump or ECU wiring. Does anyone have any diagrams to help me chase it through.

Thanks in advance
Andrew

[andrewr]

I have traced the fault to the fuel pump.

I didn't realise that the ECU switches the fuel pump off after the initial 3 seconds flush then on again once the engine starts.

I thought the pump noise stopped due to the fuel pressure being enough and therefore couldn't understand why there was no volts at the pump when I measured it.

I now need a new M400 fuel pump.