Carrier Supra 522 fault ERR.4

[AIDANMC2006]

I came up against this fault today, It wrecked my head and i still haven't it fixed. Can anybody help me with this fault?

[djbe]

I came up against this fault today, It wrecked my head and i still haven't it fixed. Can anybody help me with this fault?

Err4 refers to a breakdown in communication between microprocessor and cab command.

It is usually a problem with the cable linking the two. Just check that the lead is plugged in correctly at both ends. If still no joy check along the length of cable for damage.

[AIDANMC2006]

Hello Djbe, Thanks for your help, I replaced the cab harness as i'd a new one in stock and i still have the same problem, I replaced cab box also with secondhand one. All i'm left with now is the microprocessor

[djbe]

Well I guess you have eliminated everything to the "highest common denominator!!".

I have had to replace just one micro before for err4.

Has the customer got any other units to double check by swapping the micro over before you give him the bad news?

Drop me a pm if you need a new micro.

Good luck,
djbe.