System Diagnosis (1996 Models Equipped With 4-Speed Automatic Without Cruise Control)

Turn ignition on. Attempt to move gear selector lever from "P" position. If selector cannot be moved to another gear position, go to next step. If selector can be moved to another gear position, go to step 9).
Attempt to move gear selector lever from "P" position with brake pedal depressed. If selector can be moved to another gear position, system functions normally at this time. If selector cannot be moved to another gear position, go to next step.
Using a test light connected to ground, backprobe stoplight switch harness connector terminal No. 2 (Orange/Green wire). If test light illuminates, go to next step. If test light does not illuminate, go to step 7).
Using a test light connected to ground, backprobe stoplight switch harness connector terminal No. 4 (Blue/Green wire). Depress and hold brake pedal. If test light illuminates, go to next step. If test light does not illuminate, check stoplight switch for proper adjustment. If adjustment is okay, replace stoplight switch.
Disconnect shift lock solenoid. Using a test light connected to ground, probe shift lock solenoid harness connector terminal No. 2 (Blue/Green wire). Depress and hold brake pedal. If test light illuminates, go to next step. If test light does not illuminate, repair open in Blue/Green wire between shift lock solenoid and stoplight switch.
Turn ignition off. Using a DVOM, measure resistance between chassis ground and shift lock solenoid harness connector terminal No. 1 (Black wire). If resistance is .3 ohms or less, replace shift lock solenoid. If resistance is greater than .3 ohms, repair open in Black wire between shift lock solenoid and chassis grounding point (G202).
Ensure gear selector is in "P" position. Using a test light connected to ground, backprobe Transmission Range (TR) switch harness connector terminal No. 7 (Blue/Red wire). If test light does not illuminate, go to next step. If test light illuminates, repair open in Blue/Red wire or Orange/Green wire between TR switch and stoplight switch.
Using a test light connected to ground, backprobe TR switch harness connector terminal No. 6 (Yellow wire). If test light illuminates, replace TR switch. If test light does not illuminate, repair open in Yellow wire between TR switch and instrument panel fuse block.
Disconnect shift lock solenoid. Using a test light connected to ground, probe shift lock solenoid harness connector terminal No. 2 (Blue/Green wire). If test light does not illuminate, replace shift lock solenoid. If test light illuminates, check stoplight switch for proper adjustment. If adjustment is okay, repair Blue/Green wire between stoplight switch and shift lock solenoid for a short to power.