525 '89a vs '89m instrument cluster swap?

[Gene in NC]

525 '89a vs '89m instrument cluster swap?

OK to swap 525 instrument cluster '89 5s (3/89) into '89 at (12/88)?

AT cluster fuel and temp gauge have become intermittent with alarm chine sounding continuously when gauges not operating.

I own both cars.

[Ross]

Early cars had the coding plug in the wiring harness rather than being inside the cluster. Unless your cars straddle the change date it should work fine.
If you need the gauges I have a spare cluster I'd be happy to cannibalize for you.

[Gene in NC]

Guages are OK. Problem is they don't activate without the jury rig procedure. Occasionally they will also, momentarily peg.

[shogun]

more in detail please. Which production months? Which back plate colour? According to Johan's site:

start ->02/89 Grey HML 075 2048 bytes No self test or diagnosis via Modic. Stops at 299960. code plug is non-standard
02/89 -> 09/90 White PIC 93C46 1024 bytes Self test + diagnosis via Modic. Code plug is standard EPROM
09/90 -> end Blue PIC 93C56 2048 bytes Self test + diagnosis via Modic. Code plug is standard EPROM


so in case both are white back plate, change the cluster and install the coding plug from the old to the new cluster.