4. Selector Lever Moved to "N", Auto/Cruise Won't Cancel

Park/Neutral Position Switch Circuit:

CIRCUIT OPERATION
This circuit transmits the "N" or "P" position signal of the park/neutral position switch to the auto-cruise control-ECU. When the park/neutral position switch is at the "N" or "P" position, auto-cruise control-ECU terminal number 13 will receives 0 volt.

TECHNICAL DESCRIPTION (COMMENT)
The cause is probably an open-circuit in the output signal circuit in "N" range.

TROUBLESHOOTING HINTS
- Malfunction of the park/neutral position switch.
- Damaged harness or connector.
- Malfunction of the auto-cruise control-ECU.

DIAGNOSIS

Required Special Tool:
- MB991223: Harness Set

STEP 1. Check the output circuit voltage at park/neutral position switch connector B-16 by backprobing.
1. Do not disconnect park/neutral position switch connector B-16.
2. Turn the ignition switch to the "ON" position.

3. Measure the voltage between terminal 10 and ground by backprobing.
- Voltage should be battery positive voltage. (When select lever is in a position other than "N" range.)
- Voltage should be 0.5 volts or less. (When select lever is in "N" range.)

4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the voltage within specifications?

YES: Check that the malfunction is eliminated. If the malfunction is eliminated, replace the auto-cruise control-ECU. Then check that the malfunction is eliminated.

NO: Go to Step 2.

STEP 2. park/neutral position switch connector B-16.

Q: Is the connector damaged?

YES: Repair or replace connector. Refer to Harness Connector Inspection. Then check that the malfunction is eliminated.

NO: Go to Step 3.

STEP 3. Check the circuit at the park/neutral position switch.
1. Disconnect the park/neutral position switch connector B-16.

2. Measure the continuity park/neutral position switch connector terminals.

Q: Is the continuity meet the table shown?

YES: Go to Step 4.

NO: Replace the park/neutral position switch. Refer to Transmission. Then check that the malfunction is eliminated.

STEP 4. Check the output circuit voltage at auto-cruise control-ECU connector C-107 by backprobing.
1. Do not disconnect auto-cruise control-ECU connector C-107.
2. Turn the ignition switch to the "ON" position.

3. Measure the voltage between terminal 13 and ground by backprobing.
- Voltage should be battery positive voltage. (When select lever is in a position other than "N" range.)
- Voltage should be 0.5 volts or less. (When select lever is in "N" range.)

4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the voltage within specifications?

YES: Check that the malfunction is eliminated. If the malfunction is eliminated, replace the auto-cruise control-ECU. Then check that the malfunction is eliminated.

NO: Go to Step 5.

STEP 5. Check auto-cruise control-ECU connector C-107.

Q: Is the connector damaged?

YES: Repair or replace connector. Refer to Harness Connector Inspection. Then check that the malfunction is eliminated.

NO: Go to Step 6.

STEP 6. Check intermediate connector C-105.

Q: Is the connector damaged?

YES: Repair or replace connector. Refer to Harness Connector Inspection. Then check that the malfunction is eliminated.

NO: Go to Step 7.

STEP 7. Check the harness wire between park/neutral position switch connector B-16 terminal 10 and auto-cruise control-ECU connector C-107 terminal 13.

Q: Is any harness wire between park/neutral position switch connector B-16 terminal 10 and auto-cruise control-ECU connector C-107 terminal 13 damaged?

YES: Repair the harness wire and then check that the malfunction is eliminated.

NO: Check that the malfunction is eliminated. If the malfunction is eliminated, replace the auto-cruise control-ECU. Then check that the malfunction is eliminated.