Code No. B2514 Height sensor power supply error


caution Before replacing the ECU, ensure that the power supply circuit, the earth circuit and the communication circuit are normal.












DIAGNOSTIC FUNCTION


If a trouble occurs in height sensor, headlamp automatic levelling system warnings are displayed on the multi information display and code No. B2514 is stored.

JUDGEMENT CRITERIA


The headlamp automatic levelling-ECU detects the power supply error of the height sensor (less than 4.2 V, or 5.8 V or more) for 1 second or longer continuously.

PROBABLE CAUSES



DIAGNOSIS PROCEDURE

STEP 1. Connector check: A-01 connector assembly connector, C-14 headlamp automatic levelling-ECU connector

Q. Is the check result normal?

Go to Step 2.

Repair the defective connector.

STEP 2. Voltage measurement at the A-01 connector assembly connector.
(1)Disconnect the connector, and measure at the wiring harness-side connector.
(2)Turn the ignition switch to the ON position.
(3)Voltage between the A-01 connector assembly connector terminal No. 2 and the body earth
OK: 5 V

Q. Is the check result normal?
Go to Step 4.
Go to Step 3.

STEP 3. Wiring harness check between the A-01 connector assembly connector terminal No. 2 and the C-14 headlamp automatic levelling-ECU connector terminal No. 21.

  • Check the power supply lines for short circuit.

Q. Is the check result normal?
Go to Step 4.
Repair the wiring harness.

STEP 4. Check whether the diagnosis code is reset.

Q. Is diagnosis code No. B2514 set?
Go to Step 5.
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to cope with Intermittent Malfunctions ).

STEP 5. Connector check: F-02 rear height sensor connector, C-14 headlamp automatic levelling-ECU connector

Q. Is the check result normal?
Go to Step 6.
Repair the defective connector.

STEP 6. Voltage measurement at the F-02 rear height sensor connector.
(1)Disconnect the connector, and measure at the wiring harness-side connector.
(2)Turn the ignition switch to the ON position.
(3)Voltage between the F-02 rear height sensor connector terminal No. 1 and the body earth
OK: 5 V

Q. Is the check result normal?
Go to Step 8.
Go to Step 7.

STEP 7. Wiring harness check between the F-02 rear height sensor connector terminal No. 1 and the C-14 headlamp automatic levelling-ECU connector terminal No. 20.
note Before the wiring harness check, check the intermediate connectors C-67, D-12 and F-03, and then repair that if necessary.

  • Check the power supply lines for short circuit.

Q. Is the check result normal?
Go to Step 8.
Repair the wiring harness.

STEP 8. Check whether the diagnosis code is reset.

Q. Is diagnosis code No. B2514 set?
Go to Step 9.
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to cope with Intermittent Malfunctions ).

STEP 9. M.U.T.-III data list
Disconnect the front and rear height sensor connector, and check the power supply voltage to the height sensor.
Item No.
 Item name
 Normal condition
Item 3
 HS power supply voltage
 5 V
OK: Normal condition is displayed.

Q. Is the check result normal?
Go to Step 10.
Replace the headlamp automatic levelling-ECU.

STEP 10. Rear height sensor check
Check the rear height sensor for the internal failure.

(1)Disconnect the rear height sensor connector and connect the special tool test harness (MB991658) as shown.
(2)Turn the ignition switch to the ON position.
(3)Measure the voltage of sensor connector terminal No. 1.
OK: 5 V

Q. Is the check result normal?

Go to Step 11.

Replace the rear height sensor.

STEP 11. Check whether the diagnosis code is reset.

Q. Is diagnosis code No. B2514 set?
Replace the headlamp automatic levelling-ECU.
The diagnosis is complete.