Check Input Signal Circuit

Turn ignition off. Disconnect ECM and A/T control unit harness connectors. Using an ohmmeter, check continuity between ECM harness connector terminal No. 6 and A/T control unit harness connector terminal No. 45 (Red wire). If no continuity exists, repair open in Red wire. If continuity exists, check ECM and A/T control unit harness and connectors for damage or corrosion. Repair or replace as necessary and retest system.