megane fusebox

[ninja123]

Got a megane with water in engine bay fuse box.
Tried a used one, but car not starting, does this unit need coding or just plug & play??

ninja

[morfej]

It's just plug and play, no coding. Find a good one

Post a picture or any numbers.

br

[albertros]

HI,
if its a 2002 on shape they are plug and play. They do contain the vin number but it doesn't seem to matter.
There are different configs N2 N3 ect but itseems to be software generated in a good old eeprom. May be worth swapping but I doubt it will make any difference to it starting.

Does it crank?

[Meat-Head]

under hood - plug and pray

under dash swap 93C?? eeprom and pray

[ninja123]

I have put a fuse box from a running car and still the same.

Press start button and cooling fan starts and elec error displayed on dash.

I have no output from engine ECU.

I have a sh1t wiring diagram, and have checked ecu earths to 3 pins on ecu h1,h4 and g1, all ok.

But I can only find 1 live to ECU from my sh1t diagram, pin D1, which is live when start button pressed.

Anyone know if anymore lives/earths to power this ecu?

thanks in advance, ninja

[Meat-Head]

OK - we had one of these many many many post's ago.

WRENCH passenger front wheel off - stick on ebay

lift the fusebox -

wrench bumper off (VERY VERY VERY EASY)

The loom had chaffed 'under the passenger head light' - think it was a glowworm fault.

for fans to come on sounds like loss of feed to ecu - DUH! - you just said that!

[bonecrusher]

check fuses on battery and battery clamp

[ninja123]

check fuses on battery and battery clamp

Got all earths and power to ecu, so fuses are ok....

ninja

[teuton]

But I can only find 1 live to ECU from my sh1t diagram, pin D1, which is live when start button pressed.
thanks in advance, ninja

As general rule, you should have at least one permanent live feed (30) and one ignition switched live feed (15)on any ecu.

[Ashraf6119]

Check this 30 amp fuse near B+ battery terminal showing in the picture which is for power supply to the engine bay fuse box............

[ninja123]

Fuses are ok, im only getting 4-5 volts from underbonnet fuse box, should be battery voltage.

It appears to come from a unit incorped into fuse box called engine switching protection unit, so unless my 'new' fusebox is faulty, I need to star looking at where this unit takes its supply from..............

ninja

[Ashraf6119]

Fuses are ok, im only getting 4-5 volts from underbonnet fuse box, should be battery voltage.

It appears to come from a unit incorped into fuse box called engine switching protection unit, so unless my 'new' fusebox is faulty, I need to star looking at where this unit takes its supply from..............

ninja

Hello,

That 30 amp fuse in AD picture is that where the fuse box gets it power from............

Can you check if you have 12V at the 13 mm nut on fuse box............

[ninja123]

Yes mate, battery voltage after all 3 maxi fuses, tested under load as these slow blow fuses can still read ok with a multi meter, but they are defo ok, even bypassed them to be sure.

So, looks like another faulty fuse box, even though it came off a 'runner'

Would still like to know what this 'engine protection unit' actually does?

ninja

[Ashraf6119]

Have you checked the wiring loom near the battery which is going to Engine ECU............There is yellow and orange wire do brake and cause this kind of problem.............

Open that loom till near the front and look there for any broken wires............

[ninja123]

Got this going today too!

Heres explanation, It may help others in the future:-

In engine bay fuse box, there is a black 4 pin multiplug, pin 4 for low speed fan, pin 3 is output to starter motor solenoid, pins 2&1 should be +12v when ign turned on, but was only getting between 3 & 5 volts.

Attatched a wire from an ign live source in fuse box to ONE of the 2 pins and works great!

These two pins feed ecu, injectors and cam sensor.

Still at a loss as to where the actual fault lies, I still think I must have TWO bad fuse boxes!!

Anyhow, payment taken and im in the pub

ninja