Operation CHARM: Car repair manuals for everyone.

A: Shift Solenoids



PINPOINT TEST A: DIAGNOSTIC TROUBLE CODES 621, 622 AND 641: SOLENOID CIRCUIT FAILURES; 645, 646, 647 AND 648: INCORRECT GEAR RATIO OBTAINED

This Pinpoint Test is designed to diagnose the shift solenoid electrical system ONLY.
To prevent replacement of good components, note that the following areas may be at fault:
- Engine -- Performance, cooling, brakes
- Electrical -- Battery, input sensors, wiring harnesses
- Transaxle -- Internal transaxle components, linkage, cooling

This Pinpoint Test is designed to diagnose the following components:
- Transmission Wiring Harness, SS1, SS2, VPWR, SS3
- Powertrain Control Module (PCM) - 12A650

Refer to the following schematic and charts when performing the Pinpoint Test steps.