Inspection Procedure O-5

ETACS-ECU does not Receive "R" Position Signal from the Transmission Range Switch .

Transmission Range Switch Input Circuit Part 1:

Transmission Range Switch Input Circuit Part 2:

CIRCUIT OPERATION
The ETACS-ECU operates the rear wiper according to signal from the transmission range switch.

TECHNICAL DESCRIPTION (COMMENT)
If the signal is not normal, the rear wiper does not operate consecutively twice when the selector lever is moved to the "R" position with the rear wiper on. If the signal is not normal, the transmission range switch or the ETACS-ECU may be defective.

NOTE: The transmission range switch is shared with the automatic transmission control system. If this problem is not solved, carry out the troubleshooting regarding the automatic transmission control system. Diagnostic Strategies

TROUBLESHOOTING HINTS
- Malfunction of the transmission range switch
- Malfunction of the ETACS-ECU
- Damaged harness wires or connectors

DIAGNOSIS

Required Special Tool:
- MB991223: Test Harness Set
















STEP 1. Check the transmission range switch.
Disconnect transmission range switch connector B-41. Then check continuity between the switch terminals.

Q: Is the transmission range switch in good condition?

YES: Go to Step 2.

NO: Replace the transmission range switch. If the rear wiper operates normally, it indicates that a correct "R" position signal is sent from the transmission range switch.













STEP 2. Check at transmission range switch connector B-41 in order to check the ignition switch (IG1) line of the power supply to the transmission range switch.

1. Disconnect transmission range switch connector B-41, and measure at the wiring harness side.
2. Turn the ignition switch to the "ON" position.
3. Measure the voltage between terminal 8 and ground.
- The measured value should be approximately 12 volts (battery positive voltage).

Q: Does the measured voltage correspond with this range?

YES: Go to Step 5.

NO: Go to Step 3.










STEP 3. Check transmission range switch connector B-41 for damage.

Q: Is transmission range switch connector B-41 in good condition?

YES: Go to Step 4.

NO: Repair or replace the connector. Refer to Harness Connector Inspection. If the rear wiper operates normally, it indicates that a correct "R" position signal is sent from the transmission range switch.
















STEP 4. Check the wiring harness between transmission range switch connector B-41 (terminal 8) and the ignition switch (IG1).

NOTE: Also check junction block connectors C-111, C-112 and intermediate connector C-28. If junction block connectors C-111, C-112 or intermediate connectors C-28 is damaged, repair or replace the connector as described in Harness Connector Inspection.

Q: Is the wiring harness between transmission range switch connector B-41 (terminal 8) and the ignition switch (IG1) in good condition?

YES: No action to be taken.

NO: Repair the wiring harness. If the rear wiper operates normally, it indicates that a correct "R" position signal is sent from the transmission range switch.













STEP 5. Check transmission range switch connector B-41 and ETACS-ECU connector C-117 for damage.

Q: Are transmission range switch connector B-41 and ETACS-ECU connector C-117 in good condition?

YES: Go to Step 6.

NO: Repair or replace the connector. Refer to Harness Connector Inspection. If the rear wiper operates normally, it indicates that a correct "R" position signal is sent from the transmission range switch.
















STEP 6. Check the wiring harness between transmission range switch connector B-41 (terminal 7) and ETACS-ECU connector C-117 (terminal 39).

NOTE: Also check intermediate connector C-28. If intermediate connectors C-28 is damaged, repair or replace the connector as described in Harness Connector Inspection.

Q: Is the wiring harness between transmission range switch connector B-41 (terminal 7) and ETACS-ECU connector C-117 (terminal 39) in good condition?

YES: Replace the ETACS-ECU. If the rear wiper operates normally, it indicates that a correct "R" position signal is sent from the transmission range switch.

NO: Repair the wiring harness. If the rear wiper operates normally, it indicates that a correct "R" position signal is sent from the transmission range switch.