Troubleshooting Hints - Turbo Hydra-Matic 4T60-E Transaxle

Fig.3 Wiring Diagram:

Fig.4 BTSI Diagnosis Chart (Part 1 Of 2):

Fig.4 BTSI Diagnosis Chart (Part 2 Of 2):

BRAKE TRANSAXLE SHIFT INTERLOCK (BTSI)
1. Verify brake light operation.
2. If brake lights do not operate, refer to Fig. 3 for wiring diagram and Fig. 4 for diagnostic procedure.
3. Check for proper installation of aftermarket equipment or for broken or partially broken wires inside of insulation. This could cause system failures, but not be indicated in a continuity or voltage check.