W T E C I I I E L E C T R O N I C C O N T R O L S T R O U B L E S H O O T I N G M A N U A L
Figure 515. Solenoid Resistance vs. Temperature
1. Make sure the transmission connector is tightly connected. If the connector is properly connected,
disconnect the wiring harness at the transmission. Check the connector for corroded or damaged
terminals. Clean or replace as necessary.
2. Test each solenoid circuit at the transmission connector for shorts between the solenoid circuit be-
ing diagnosed and all other terminals in the connector. This test may be simplified by using the
J41612 test tool. Refer to the system schematic and/or chart to identify wires in the internal har-
ness which are connected. If a short is found, isolate and repair the short. The short will probably
be in the internal wiring harness.
3. If multiple code 42s occur (4212, 4213, 4214, 42 12, 4216, 4222, and 4224), and wiring and
solenoids check okay, the A-Hi driver is probably failed open.
4. Replace the ECU. If replacing the ECU corrects the problem, reinstall the original (bad) ECU to
confirm that the problem is in the ECU. If the problem recurs, reinstall the new ECU to complete
5. If code 4221 occurs repeatedly and the F solenoid and wiring checks okay, the F-Hi or F-Lo driver
may be failed open. Follow Step (4) above.
6. If codes 4223 and 4226 occur repeatedly and solenoids and wiring check okay, the H and N-Hi
driver may be failed open. Follow Step (4) above.
7. If the short is not found at the transmission connector, disconnect the transmission T harness
connector at the ECU and check the wires of the solenoid circuit for shorts between the solenoid
wires. If the short is found in one of the wires, isolate and repair it. Use a spare wire, if available,
or provide a new wire (St. Clair P/N 200153 may be used for this purpose).
CODE 42 XX SHORT-TO-BATTERY IN SOLENOID CIRCUIT (Figure 515)