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 rear height sensor, headlamp automatic levelling system warnings are displayed on the multi information display and code No. B2516 is stored.
JUDGEMENT CRITERIA
The headlamp automatic levelling-ECU detects the error of the signal voltage from the rear height sensor (less than 0.7 V, or 4.2 V or more) or 1 second or longer continuously.
PROBABLE CAUSES
Malfunction of the rear height sensor
Malfunction of the rear height sensor installation
Malfunction of the headlamp automatic levelling-ECU
Damaged harness wires and connectors
DIAGNOSIS PROCEDURE
STEP 1. M.U.T.-III diagnosis code
Check if diagnosis code No. B2514 is set.
Q.
Is diagnosis code No. B2514 set?
Perform the troubleshooting of the diagnosis code No. B2514.
Go to Step 2.
STEP 2. Rear height sensor installation status check
Check that the rear height sensor is installed properly.
STEP 4. Voltage measurement at the D-117 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 D-117 rear height sensor terminal No. 1 and the body earth OK: 5 V
Q.
Is the check result normal?
Go to Step 6.
Go to Step 5.
STEP 5. Wiring harness check between the D-117 rear height sensor connector terminal No. 1 and the C-112 headlamp automatic levelling-ECU connector terminal No. 20.
note
Before the wiring harness check, check the intermediate connectors C-131 and D-116, and repair that if necessary.
Check the power supply line for open circuit.
Q.
Is the check result normal?
Replace the headlamp automatic levelling-ECU
Repair the wiring harness.
STEP 6. Resistance measurement at the D-117 rear height sensor connector.
(1)Disconnect the connector, and measure at the wiring harness side.
(2)Measure the resistance between the D-117 rear height sensor connector terminal No. 3 and the body earth. OK: Continuity exists (2 Ω or less)
Q.
Is the check result normal?
Go to Step 8.
Go to Step 7.
STEP 7. Wiring harness check between the D-117 rear height sensor connector terminal No. 3 and the C-112 headlamp automatic levelling-ECU connector terminal No. 16.
note
Before the wiring harness check, check the intermediate connectors C-131 and D-116, and repair that if necessary.
Check the earth line for open circuit.
Q.
Is the check result normal?
Replace the headlamp automatic levelling-ECU
Repair the wiring harness.
STEP 8. Wiring harness check between the D-117 rear height sensor connector terminal No. 2 and the C-112 headlamp automatic levelling-ECU connector terminal No. 17.
note
Before the wiring harness check, check the intermediate connectors C-131 and D-116, and repair that if necessary.
Check the signal lines for open or short circuit.
Q.
Is the check result normal?
Go to Step 9.
Repair the wiring harness.
STEP 9. rear height sensor check
Check that the rear height sensor is normal (Refer to ).
Q.
Is the check result normal?
Go to Step 10.
Replace the rear height sensor.
STEP 10. M.U.T.-III data list
Check the rear height sensor for the signal voltage.
Item No.
Item name
Normal condition
Item 5
Rear HS signal voltage
0.7 V - 4.1 V
OK: Normal condition is displayed.
Q.
Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to cope with Intermittent Malfunctions ).
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Perform the troubleshooting of the diagnosis code No. B2514.
Go to Step 2.
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