DTC 23
DTC 23: Height Sensor Power Supply Short To GroundCAUTION: Before replacing the ECU, ensure that the communication circuit is normal.
Height Sensor Power Supply Circuit (Part 1):
Height Sensor Power Supply Circuit (Part 2):
TROUBLE JUDGMENT
If the front height sensor, rear height sensor power supply, or ground line is short-circuited, DTC 23 is set.
TECHNICAL DESCRIPTION (COMMENT)
The front height sensor, the rear height sensor, the headlight automatic leveling-ECU, or wiring harness and connectors between the front/rear height sensor and the headlight automatic leveling-ECU may have a problem.
TROUBLESHOOTING HINTS
- Malfunction of the front height sensor
- Malfunction of the rear height sensor
- Malfunction of the headlight automatic leveling-ECU
- The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector
DIAGNOSIS
Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: Vehicle Communication Interface (V.C.I.)
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A (Vehicles with CAN communication system)
STEP 1. Check front height sensor connector A-04 and headlight automatic leveling-ECU connector C-110 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Are front height sensor connector A-04 and headlight automatic leveling-ECU connector C-110 in good condition?
YES : Go to Step 2.
NO : Repair the damaged parts.
STEP 2. Check the wiring harness between front height sensor connector A-04 (terminal No. 1/3) and headlight automatic leveling-ECU connector C-110 (terminal No. 15/19).
NOTE: Before the wiring harness check, check the intermediate connector A-57, and repair that if necessary.
Q: Is wiring harness between front height sensor connector A-04 (terminal No. 1/3) and headlight automatic leveling-ECU connector C-110 (terminal No. 15/19) in good condition?
YES : Go to Step 3.
NO : Repair the wiring harness.
STEP 3. Using scan tool MB991958, Check whether the diagnostic trouble code is reset.
CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.
1. Connect scan tool MB991958. Refer to "How to connect scan tool." Scan Tool Connecting
2. Turn the ignition switch to the "ON" position.
3. Erase the DTC.
4. Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
5. Check if DTC is set.
Q: Is DTC 23 set?
YES : Go to Step 4.
NO : The trouble, such as a poor connector connection from the front height sensor to headlight automatic leveling-ECU or an open circuit of wiring harness, can be an intermittent malfunction. (Refer to general (body and chassis) - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction.)
STEP 4. Check rear height sensor connector D-118 and headlight automatic leveling-ECU connector C-110 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Are rear height sensor connector D-118 and headlight automatic leveling-ECU connector C-110 in good condition?
YES : Go to Step 5.
NO : Repair the damaged parts.
STEP 5. Check the wiring harness between rear height sensor connector D-118 (terminal No. 1/3) and headlight automatic leveling-ECU connector C-110 (terminal No. 16/20).
NOTE: Before the wiring harness check, check the intermediate connectors C-129 and D-117, and then repair that if necessary.
Q: Is wiring harness between rear height sensor connector D-118 (terminal No. 1/3) and the headlight automatic leveling-ECU connector C-110 (terminal No 16/20) in good condition?
YES : Go to Step 6.
NO : Repair the wiring harness.
STEP 6. Using scan tool MB991958, Check whether the diagnostic trouble code is reset.
1. Turn the ignition switch to the "ON" position.
2. Erase the DTC.
3. Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
4. Check if DTC is set.
Q: Is DTC 23 set?
YES : Go to Step 7.
NO : The trouble, such as a poor connector connection from the rear height sensor to headlight automatic leveling-ECU or an open circuit of wiring harness, can be an intermittent malfunction. (Refer to general (body and chassis) - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction.)
STEP 7. Check front height sensor.
Check that the front height sensor is normal. Front Height Sensor Check
Q: Do front height sensor work normal?
YES : Go to Step 8.
NO : Replace the front height sensor.
STEP 8. Using scan tool MB991958, Check whether the diagnostic trouble code is reset.
1. Turn the ignition switch to the "ON" position.
2. Erase the DTC.
3. Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
4. Check if DTC is set.
Q: Is DTC 23 set?
YES : Go to Step 9.
NO : The procedure is complete.
STEP 9. Check rear height sensor.
Check that the rear height sensor is normal. Rear Height Sensor Check
Q: Does the rear height sensor work normal?
YES : Go to Step 10.
NO : Replace the rear height sensor.
STEP 10. Using scan tool MB991958, Check whether the diagnostic trouble code is reset.
1. Turn the ignition switch to the "ON" position.
2. Erase the DTC.
3. Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
4. Check if DTC is set.
Q: Is DTC 23 set?
YES : Replace the headlight automatic leveling-ECU.
NO : The procedure is complete.