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Posting this here instead of the Fleetwood forum for increased visibility. Mods feel free to move if needed but I feel this is a fairly high level VATS discussion. My 94 Fleetwood is currently inop due to a passkey failure that I’ve been unable to resolve. Need some input on next steps to try or point out something obvious I’ve missed.

Background: Car has had intermittent no start passkey events and passkey light staying on after successful ignition events for several months. I’ve swapped to a new key and later did the resistor bypass mod under the column to no change in behavior. Car would go a few days without errors and then start acting up again. I suspect that there is a short/break in one of the circuits that run through the steering column. While early failures exhibited the worn key/cylinder behavior (car started up on 2nd or 3rd try) it evolved into a failure that could be quickly solved only by adjust and turning the steering wheel. I have seen historical diagnostic codes for "PASS KEY FAULT" telltale circuit (circuit shorted to battery) (130) throughout even after clearing them. (For the record also have had a fairly constant CCM error code 23 DIL enable circuit (circuit open or shorted to ground) along with a historical entry for this as well. Seen historical entries for 22 DIL enable circuit (circuit shorted to battery) too.)

What I’ve Tried: As mentioned I’ve replaced the key, and done the resistor bypass with no change in behavior. Both worked just fine at times. Over the weekend I tested both the key pill circuit and the resistor bypass mod and validated that they both share the same resistor value. I also tested the PassKey resistor circuit that runs to the CCM for continuity by placing a 9v battery on one end and validating that I was getting 9v at the other. It successfully passed that. Even after all the futzing around under the dash (and being none to gentle) and disconnecting and reconnecting the CCM in the trunk (while massaging and inspecting the harness to include the connectors) the PassKey error persisted. I even went as far as to directly wire the resistor bypass to the back side of the CCM connecters with no effect.

Next Steps: The only two things I can see left to try is to de-pin PassKey resistor circuit from the CCM connectors and direct pin the resistor mod in rather than just pushing the wires in from the backside. The other option is swapping the CCM for a known good one (along with an appropriate resistor mod) to see if the CCM module has gone bad.

The only other part of the passkey circuit I haven’t touched is the Theft Deterrent Module relay. I’ve seen nothing in the error codes to even point me to that as being the failure point. Nor do I seem to be experiencing any of the failure behaviors described in the FSM diagnostic tree (I’ve got the factory FSM for the car) when the TDM relay is the problem.

Have I missed trying/testing anything? Are my next steps appropriate? Any input will be much appreciated.
 
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