I'd forgotten all about that test, thanks Joe. For others; this is an actual function test that's separate from check light test that's run every time you switch the ignition on. I cannot find a nice simple summary of what it does in sequence but the 2006 FSM, which refers to this as the Instrument Cluster Self Test, (beginning on page 8J-65 and scattered thru various pages to 8J-87) does discuss what the test is supposed to do with respect to various lights and gauges on the dash. For 2005 owners the FSM, which refers to this as the Instrument Cluster Actuator Test, does not provide the same level of detail but the procedure is briefly outlined beginning on page 8J-8. Oddly the separate 2005 KJ Body manual does have more detail and refers to the test as the Instrument Cluster Self Test. Go figure.

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Sold to LOST member my 05 Ltd, GDE Stg II turbo + TCM tune, SunCoast TC w. Transgo kit, Steiger window regulators, Samcos, Fumoto valve, 2nd gen filter head with Lub. Spec. bleeder, Hayden clutch & 11 blade fan, inverted spare, P-1 battery, BF Goodrich Long Trail TAs, Etecno1 glow plugs, timing belt at 50K miles/8 yrs