p38 4.6 eas problems

gregyzfr1 said:

long day spent working on rangey & achieved nothing electrics are a dark art to me but i definately have no power to pressure switch or at pin 13 on ecu the air is low now & switch has changed state where do i find the power supply? as i have no idea rave is no help either

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RAVE has all the details. I'd have to check but from memory I thought the pressure switch swich the earth line. I'll go look.
There will be no power at pin 13 unless the pressure switched is closed, it closes at 10 bar.
Is fuse 29 OK? The delay timer relay under the passenger seat will also stop the system operating and interupts the supply to the pressure switch.

checked fuse 29 looked good but replaced it, no change also orange wire to compressor goes live with engine running, should it?

gregyzfr1 said:

checked fuse 29 looked good but replaced it, no change also orange wire to compressor goes live with engine running, should it?

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Remove and check the timer relay under the passenger seat.
I think in that case the compressor should run, black is ground, the small wire give a ground signal to the EAS ECU via the thermal switch and the fat orange wire goes direct to the motor.

i have removed relay under seat & this throws up a fault so guessing its ok as for orange wire i was under the impression that this goes to thermal cut out & green wire runs to compressor i could be wrong as i say electrics are a mystery to me

gregyzfr1 said:

i have removed relay under seat & this throws up a fault so guessing its ok as for orange wire i was under the impression that this goes to thermal cut out & green wire runs to compressor i could be wrong as i say electrics are a mystery to me

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Thin Black/Purple is thermal switch, Black is Ground, Orange is switched live, It's a fat wire is it not?
If it's live the motor should run, if it does not either the motor is stuffed or there is a bad earth or the connector is faulty.
On the inner wing by the EAS box, there are 2 earth studs, check both.

Look at RAVE, Circuit, section S1, page 5 on my copy.

the fat orange wire connects to the thin black/purple wire there is a green wire & a black wire i know there is nothing wrong with the motor as it runs with diagnostics or by bridging terminals at relay 20

gregyzfr1 said:

the fat orange wire connects to the thin black/purple wire there is a green wire & a black wire i know there is nothing wrong with the motor as it runs with diagnostics or by bridging terminals at relay 20

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OK, you are looking at the motor side of the connector, I'm looking at the other side. On the motor the thin orange wire is the thermal switch and connects to the black/purple, it should be at ground potential. Black at the motor is ground, connects to black, Green at the motor is switched positive.
For the motor to run from ECU control, the orange motor wire must be at ground potential as this signals to the ECU that there is no overheat, the black wire must also be at ground potential, the green wire should have 12 volts on it from the ECU but only if the thermal switch is OK and the orange wire is at ground.