Code No. B1551: SRS warning lamp circuit malfunction (Lamp does not Illuminate)
















OPERATION




TROUBLE JUDGEMENT



PROBABLE CAUSES



  • Damaged wiring harnesses of connectors
  • Malfunction of the SRS-ECU
  • Malfunction of the combination meter

DIAGNOSIS PROCEDURE

STEP 1. Voltage measurement at the B-101 combination meter connector.
(1)Check that the negative auxiliary battery terminal is disconnected. If the negative auxiliary battery terminal is connected, disconnect it.
(2)Disconnect the B-101 combination meter connector.
(3)Connect the negative auxiliary battery terminal.
(4)Electric motor switch to the "ON" position.
(5)
caution Do not insert a test probe into the terminal from its front side directly as the connector contact pressure may be weakened.
Take the measurements below at the B-101 combination meter connector.

  • Voltage between terminal No. 2 and body earth
OK: 9 V or more
(6)Disconnect the negative auxiliary battery terminal.

Q. Is the check result normal?
Go to Step 3
Go to Step 2

STEP 2. Check the harness for open circuit between electric motor switch and B-101 combination meter connector.
note Prior to the wiring harness inspection, check junction block connector B-302 and B-305, and repair if necessary.

  • The SRS warning lamp circuit inspection for open circuit

Q. Is the check result normal?
An intermittent malfunction is suspected (Refer to GROUP 00, How to Cope with Intermittent Malfunction ).
Repair the harness wires. Then go to Step 5.

STEP 3. Check the harness for short circuit between the B-101 combination meter connector (terminal No.15) and B-112 SRS-ECU connector (terminal No.39).
note Prior to the wiring harness inspection, check B-120 intermediate connector and earth connector B-25 and B-11 <LHD>, and repair if necessary.

  • The SRS-ECU signal lines inspection for short to earth

Q. Is the check result normal?
Go to Step 4
Repair the harness wires.Then go to Step 5

STEP 4. Check the SRS warning lamp.
(1)Check that the negative auxiliary battery terminal is disconnected. If the negative auxiliary battery terminal is connected, disconnect it.
(2)Disconnected the B-112 SRS-ECU connector.
(3)Connect the negative auxiliary battery terminal.
(4)Electric motor switch to the "ON" position.

Q. Does the SRS warning lamp illuminate?
Go to Step 5
Replace the combination meter (Refer to GROUP 54A, Combination Meter ).

STEP 5. Check whether the diagnosis code is reset.

Q. Is the diagnosis code set?
Replace the SRS-ECU (Refer to ).
An intermittent malfunction is suspected (Refer to GROUP 00, How to Cope with Intermittent Malfunction ).