P38A Air Suspension Playing Up 27 fault codes

Saint.V8 said:

If the faults conflict with themselves i.e. it says a valve is open and closed at the same time you have poor communication with the ECU, if your using a T4 Testbook, then I can only imagine the Diagnostic connection needs a clean.....pop the valance off and look at the wired side of the socket too as they can corrode there also.

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jacktw said:

How do you go about diagnosing the fault then?

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jacktw said:

How do you go about diagnosing the fault then?

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Saint.V8 said:

Bloody jinx again Tony....

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Saint.V8 said:

Are you getting conflicting faults as I said above? If you are, you are not getting a good communication link to the EAS ECU....you will need to check either the software and hardware you are using is setup correctly or the diagnostic port and the wiring thereto needs looking at....

Once you have good communication to the EAS ECU, and can read a comprehensible list of faults, then fault diagnosis can begin.....unfortunately with a jumble of random faults that conflict it would be unwise to speculate.

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Saint.V8 said:

Are you getting conflicting faults as I said above? If you are, you are not getting a good communication link to the EAS ECU....you will need to check either the software and hardware you are using is setup correctly or the diagnostic port and the wiring thereto needs looking at....

Once you have good communication to the EAS ECU, and can read a comprehensible list of faults, then fault diagnosis can begin.....unfortunately with a jumble of random faults that conflict it would be unwise to speculate.

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wammers said:

By getting good comms with the ECU. Check the OBDII socket and connections and fuse 33 5AMP in engine bay fuse box. A long list of faults that contradict each other is a sure sign of bad comms with the EAS ECU. If you have the same valve open and closed at the same time that is a sure sign of bad comms. Because those two faults cannot be correct when listed at the same time. As for pressure switch fault, check connectors in blocks under valve block for good contact. Pressure switches do fail but very rarely. What exactly is the wording of the pressure switch fault. If it says constantly high it maybe a problem with the driver pack. If it says constantly low it may just be that the compressor is knackered.

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oakey said:

Maybe its Schrodinger's valve?

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