Heated Seats Inoperative Due To Key-In Ignition Switch Input

NOTE: After making any repairs, perform MEMORY HEATED SYSTEM VERIFICATION TEST under VERIFICATION TESTS.

Possible Causes:

Observe The Key-In Ignition Switch Status
Ignition Switch Open
Key-In Ignition Switch Ground Circuit Open
Key-In Ignition Switch Sense Circuit Open
BCM Incorrect Key-In Ignition Switch Status

Testing

Turn ignition off. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Using scan tool, select BODY COMPUTER, then INPUT. Using scan tool, read KEY-IN IGNITION SWITCH status. If scan tool does not display KEY-IN IGN: CLOSED, go to next step. If scan tool displays KEY-IN IGN: CLOSED, fault may be intermittent. Check related wiring and connectors for poor connections or damage to wiring harness. See WIRING DIAGRAMS . Repair any problems found as necessary. If no problems are found, check if any Technical Service Bulletins (TSBs) apply to vehicle. If no TSBs apply, test is complete.
Turn ignition off. Disconnect ignition switch connector. Connect a jumper wire between ground and ignition switch connector terminal No. l, key-in ignition switch sense circuit (Light Blue wire). See Figure . Using scan tool, read KEY-IN IGNITION status. If scan tool displays KEY-IN IGN: CLOSED, replace ignition switch. See IGNITION SWITCH under REMOVAL & INSTALLATION. If scan tool does not display KEY-IN IGN: CLOSED, leave ignition switch connector disconnected and go to next step.
Turn off all lights. Measure resistance between ground and ignition switch connector terminal No. 3, ground circuit (Black/Light Green wire). If resistance is less than 5 ohms, leave ignition switch connector disconnected and go to next step. If resistance is 5 ohms or more, repair open in Black/Light Green wire.
Disconnect Body Control Module (BCM) connector C2. Measure resistance of key-in ignition switch sense circuit (Light Blue wire) between ignition switch connector terminal No. 1 and BCM connector C2 terminal No. 24. See Figure and Figure . If resistance is less than 5 ohms, replace BCM. See BODY CONTROL MODULE under REMOVAL & INSTALLATION. If resistance is 5 ohms or more, repair open in Light Blue wire.