Test 12A: No Response From Transmission Control Module
NOTE:
For connector terminal identification and wiring diagrams, see
BODY CONTROL COMPUTER - INTRODUCTION article. Perform VERIFICATION TEST VER-1
after each repair.
CAUTION:
Always turn ignition off prior to disconnecting any module connector.
- Disconnect Transmission Control Module (TCM). TCM is located at left fenderwell, next to power distribution center in engine compartment. Turn ignition on. Using external voltmeter, measure voltage between ground and TCM connector terminal No. 11 (Red/White wire). If voltage is 10 volts or less, repair open Red/White wire. If voltage is more than 10 volts, go to next step.
- Measure voltage between ground and TCM connector terminal No. 56 (Red/Light Blue wire). If voltage is 10 volts or less, repair open Red/Light Blue wire. If voltage is more than 10 volts, go to next step.
- Turn ignition off. Using external ohmmeter, measure resistance between ground and TCM connector terminals No. 53 (Black wire) and No. 57 (Black/Red wire). If resistance of either circuit is 5 ohms or more, repair open Black or Black/Red wire. If resistance of both circuits is less than 5 ohms, go to next step.
- Turn ignition on. Using external voltmeter, measure voltage between ground and TCM connector terminal No. 43 (Violet/Yellow wire). If voltage is .5 volt or less, repair open Violet/Yellow wire. If voltage is more than 10 volts, replace TCM.