WTEC III ELECTRONIC CONTROLS TROUBLESHOOTING MANUAL S ECTION 4 — WIRE CHECK PROCEDURES Copyright © 2001 General Motors Corp. 4–1. CHECKING OPENS, SHORTS BETWEEN WIRES, AND SHORTS-TO-GROUND (Use Digital Volt/Ohmmeter J 34520-A and Jumper Wire Set J 39197) NOTE: Please refer to Paragraph 3–5 to begin the troubleshooting process. 1. Make sure all connectors are tightly connected and re-check the circuit. 2. Disconnect and inspect all connectors. 3. Thoroughly clean corroded or dirty terminals. If dirty or corroded terminals are the probable cause of the problems, reconnect the clean connectors and operate the vehicle normally. If the problem recurs, proceed with Step (4).
The cleaning solvent must not be chlorine based, contain petroleum distillates, or conduct electricity. The cleaning solvent should evaporate quickly to prevent the possibility of condensation within the connectors. Always blow or shake any excess CAUTION: cleaner from the connector before assembling it to its mating connector or hardware. Cleaner trapped in the connector can affect the connector seal. (Refer to SIL 17-TR-94 for detailed information on the recommended cleaners.) 4. Review the WTEC III wire numbering system described in Paragraph 3–4. 5. If all connectors are clean and connected correctly, determine which wires in the chassis harness are indicated by the diagnostic code.
For example, Code 41 12, indicates an open or short-to-ground in the solenoid A circuit — wires 102-T1 and 120-T4. a. Check continuity of wires 102-T1 and 120-T4 by performing the following (refer to Figure 4–1): (1) Disconnect the blue “T” connector from the ECU and disconnect the harness from the transmission main connector. At one end of the harness, using jumper wire kit J 39197 and connector probes in J 39775-CP, connect wire 102-T1 and 120-T4 to each other, being careful not to distort the termi- nals. Jumping the wires together creates a circuit between wires 102-T1 and 120-T4.
TRANSMISSION CONNECTOR WIRING HARNESS JUMPER ECU “T” CONNECTOR 0 VOLT/OHM- METER – – (VOM) + + 0 OHMS OHMS Circuit has continuity. Jumper Circuit does not have continuity due from 102 or 120 to another wire to a broken wire (open circuit). produces a complete circuit. VOM VOM reading is very high reading is near zero Ohms. (infinite Ohms or OL – overlimit). V03374.01 Figure 4–1. Open Circuit 3. Thoroughly clean corroded or dirty terminals. If dirty or corroded terminals are the probable cause of the problems, reconnect the clean connectors and operate the vehicle normally. If the problem recurs, proceed with Step (4). The con pos CAUTION:
cle Cle for cleaning solvent must not be chlorine based, contain petroleum distillates, or duct electricity. The cleaning solvent should evaporate quickly to prevent the sibility of condensation within the connectors. Always blow or shake any excess aner from the connector before assembling it to its mating connector or hardware. aner trapped in the connector can affect the connector seal. (Refer to SIL 17-TR-94 detailed information on the recommended cleaners.) 4. Review the WTEC III wire numbering system described in Paragraph 3–4. 5. If all connectors are clean and connected correctly, determine which wires in the chassis harness are indicated by the diagnostic code.
For example, Code 41 12, indicates an open or short-to-ground in the solenoid A circuit — wires 102-T1 and 120-T4. a. Check continuity of wires 102-T1 and 120-T4 by performing the following (refer to Figure 4–1): (1) Disconnect the blue “T” connector from the ECU and disconnect the harness from the transmission main connector. At one end of the harness, using jumper wire kit J 39197 and connector probes in J 39775-CP, connect wire 102-T1 and 120-T4 to each other, being careful not to distort the termi- nals. Jumping the wires together creates a circuit between wires 102-T1 and 120-T4.
TRANSMISSION CONNECTOR WIRING HARNESS JUMPER ECU “T” CONNECTOR 0 VOLT/OHM- METER – – (VOM) + + 0 OHMS OHMS Circuit has continuity. Jumper Circuit does not have continuity due from 102 or 120 to another wire to a broken wire (open circuit). produces a complete circuit. VOM VOM reading is very high reading is near zero Ohms. (infinite Ohms or OL – overlimit). V03374.01 Figure 4–1. Open Circuit