[23A] AUTOMATIC TRANSMISSION (FF) - - TROUBLESHOOTING <A/T> - DIAGNOSTIC TROUBLE CODE PROCEDURES <4G69> - Code No.15: A/T Fluid Temperature Sensor System | PRINT PAGE / INDEX / PRIOR / NEXT

| DIAGNOSTIC TROUBLE CODE PROCEDURES <4G69>

Code No.15: A/T Fluid Temperature Sensor System
OPERATION The A/T fluid temperature sensor converts the automatic fluid temperature to voltage, and send the information to the engine-A/T-ECU. The A/T fluid temperature rises, the resistance decreases. Thus, the sensor output voltage depends on the automatic fluid temperature. As the A/T fluid temperature rises, the output voltage will decrease.
DIAGNOSIS CODE SET CONDITIONS If the A/T fluid temperature sensor output voltage is 4.5 volts or more after driving for 10 minutes or more, there is an open circuit in the A/T fluid temperature sensor and diagnosis code 15 is set.
PROBABLE CAUSES Malfunction of the A/T fluid temperature sensor Damaged harness wires and connectors Malfunction of the engine-A/T-ECU
DIAGNOSIS PROCEDURE
STEP 1. MUT-II/III data list Item 15: A/T fluid temperature sensor (Refer to Data List Table ). Q: Is the check result normal? YES: Intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ). NO: Go to Step 2.
STEP 2. Measure the resistance at A/T control solenoid valve assembly connector B-21. Disconnect the connector, and measure the resistance between terminal 1 and 2 at the sensor side. OK: 16.7 - 20.5 kΩ (at 0°C) 7.3 - 8.9 kΩ (at 20°C) 3.4 - 4.2 kΩ (at 40°C) 1.9 - 2.2 kΩ (at 60°C) 1.0 - 1.2 kΩ (at 80°C) 0.57 - 0.69 kΩ (at 100°C) Q: Is the check result normal? YES: Go to Step 3. NO: Replace the A/T fluid temperature sensor.
STEP 3. Connector check: B-21 A/T control solenoid valve assembly Check for the contact with terminals. Q: Is the check result normal? YES: Go to Step 4. NO: Repair the defective connector.
STEP 4. Measure the resistance at A/T control solenoid valve assembly connector B-21. Disconnect the connector, and measure the resistance between terminal 2 and earth at the wiring harness side. OK: 2 Ω or less Q: Is the check result normal? YES: Go to Step 9. NO: Go to Step 5.
STEP 5. Measure the voltage at engine-A/T-ECU connector C-137. Connect A/T control solenoid valve assembly connector B-21. Turn the ignition switch to the ON position. Measure the voltage between engine-A/T-ECU connector C-137 terminal No.96 and earth. OK: 0.5 V or less Q: Is the check result normal? YES: Go to Step 8. NO: Go to Step 6.
STEP 6. Connector check: C-137 engine-A/T-ECU connector Check for the contact with terminals. Q: Is the check result normal? YES: Go to Step 7. NO: Repair the defective connector.
STEP 7. MUT-II/III data list Item 15: A/T fluid temperature sensor (Refer to Data List Table .) Q: Is the check result normal? YES: Intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ). NO: Replace the engine-A/T-ECU.
STEP 8. Connector check: C-137 engine-A/T-ECU connector Check for the contact with terminals. Q: Is the check result normal? YES: Go to Step 14. NO: Repair
STEP 9. Measure the voltage at A/T control solenoid valve assembly connector B-21. Disconnect the connector, and measure the voltage between terminal 1 and earth at the wiring harness side. Turn the ignition switch to the ON position. OK: 4.5 - 4.9 V Q: Is the check result normal? YES: Go to Step 7. NO: Go to Step 10.
STEP 10. Measure the voltage at engine-A/T-ECU connector C-137. Connect A/T control solenoid valve assembly connector B-21. Turn the ignition switch to the ON position. Measure the voltage between engine-A/T-ECU connector C-137 terminal No.119 and earth. OK: 3.8 - 4.0 V (at 20°C) 3.2 - 3.4 V (at 40°C) 1.7 - 1.9 V (at 80°C) Q: Is the check result normal? YES: Go to Step 12. NO: Go to Step 11.
STEP 11. Connector check: C-137 engine-A/T-ECU connector Check for the contact with terminals. Q: Is the check result normal? YES: Go to Step 7. NO: Repair the defective connector.
STEP 12. Connector check: C-137 engine-A/T-ECU connector Check for the contact with terminals. Q: Is the check result normal? YES: Go to Step 13. NO: Repair the defective connector.
STEP 13. Check the harness between A/T control solenoid valve assembly connector B-21 terminal No.1 and engine-A/T-ECU connector C-137 terminal No.119. Check the output line for short-circuited or open circuit. Q: Is the check result normal? YES: Go to Step 7. NO: Repair the wiring harness.
STEP 14. Check the harness between A/T control solenoid valve assembly connector B-21 terminal No.2 and engine-A/T-ECU connector C-137 terminal No.96. Check the earth line for open circuit. Q: Is the check result normal? YES: Go to Step 7. NO: Repair the wiring harness.

[23A] AUTOMATIC TRANSMISSION (FF) - - TROUBLESHOOTING <A/T> - DIAGNOSTIC TROUBLE CODE PROCEDURES <4G69> - Code No.15: A/T Fluid Temperature Sensor System | PRINT PAGE / INDEX / PRIOR / NEXT

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