PIC5460B

Bulletin No.: PIC5460B
Date: Mar-2016
Subject:
No Crank Key Stuck In Ignition Lock Cylinder Multiple ECM Codes And U1000 Set In Class 2 Modules
Models:
2004 - 2007 Cadillac CTS With 3.6L Engine (RPO LY7)
2004 - 2009 Cadillac SRX With 3.6L Engine (RPO LY7)
This PI was superseded to update the Conditions section. Please discard PIC5460A.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern
A customer may comment of a no crank concern or they are unable to remove their key from the ignition lock cylinder. The technician may find codes P0318,
P1629, U1040, U1064, U1153, U1192, and U1300 stored in the ECM. Other Class 2 modules may have a U0100 and/or U1000 code stored.
Recommendation/Instructions
These concerns may be caused by an Ignition 1 Power Feed (CKT 5290) or Class 2 (CKT 1807) wiring concern to the ECM.
–
If the EC Ignition relay feedback parameter in the ECM is not battery voltage, measure the voltage at the ECM fuse in the underhood fuse block. If
voltage is less than battery voltage, check to make sure the PCM is turning the relay on via CKT 5069.
–
If there is battery voltage at the ECM fuse, check Ignition 1 (CKT 5290) between the fuse and the ECM.
–
If Ignition 1 (CKT 5290) to the ECM checks OK, check for a possible open in the Class 2 (CKT 1807) to the ECM.
Note: An intermittent connection concern may be caused by a main/powertrain relay or any of the circuits listed above. If all connections and wiring are OK,
suspect a possible relay or an ECM concern.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the
remaining steps do not need to be performed.
Additional SI Keywords
U0100
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may
occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools,
safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that
your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
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