[ Model - ECLIPSE CROSS / Year - 2018 ]
2018 / ECLIPSE CROSS / EC - Workshop Manual
52 -INTERIOR AND SUPPLEMENTAL RESTRAINT SYSTEM(SRS) > 52B-SUPPLEMENTAL RESTRAINT SYSTEM (SRS) > TROUBLESHOOTING > DIAGNOSIS CODE PROCEDURES > DTC B1660 2ND SEAT (LH) PRETEN. SQUIB OPEN
Code No.B1660 Rear seat belt pre-tensioner (LH) (squib) system (open circuit of squib circuit)
 
 
cautionIf the diagnosis code B1660 is set to SRS-ECU, be sure to diagnose the CAN bus line.
 
 
OPERATION
Only when the frontal impact exceeding the threshold is simultaneously detected (turned ON) by the front impact sensor as well as by the analogue G-sensor and safing G-sensor in SRS-ECU, the electric current is supplied from SRS-ECU to the rear seat belt pre-tensioner (squib).
 
 
TROUBLE JUDGEMENT
The code is set when the open circuit occurs to the SRS-ECU rear seat belt pre-tensioner (LH) (squib) circuit.
 
 
PROBABLE CAUSES
  • Open circuit to rear seat belt pre-tensioner (LH) (squib) circuit
  • Damaged wiring harness and connector
  • Malfunction of SRS-ECU
 
 
DIAGNOSIS PROCEDURE
STEP 1. M.U.T.-IIISE CAN bus diagnostics.
Use M.U.T.-IIISE to diagnose the CAN bus lines.
Is the check result normal?
Go to Step 2.
Repair the CAN bus line (Refer to GROUP 54C - Troubleshooting ).
 
STEP 2. Check whether the diagnosis code is set again.
(1) Connect the negative battery terminal.
(2) After erasing the diagnosis code memory, check the diagnosis code again.
(3) Disconnect the negative battery terminal.
Is the diagnosis code No. B1660 set?
Go to Step 3.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).
 
STEP 3. Diagnosis check by dummy resistor connection.
(1) Check that the negative battery terminal is disconnected. If the negative battery terminal is connected, disconnect it.
 
(2) Use the flat-tipped screwdriver to pull out the locking button of harness side connector. After releasing the lock, disconnect the rear seat belt pre-tensioner (LH) harness side connector.
 
(3) Connect special tool dummy resistor (MB991865) to special tool resistor harness (MB991884).
(4) Connect the special tool resistor harness to the rear seat belt pre-tensioner (LH) harness side connector.
(5) Connect the negative battery terminal.
(6) After erasing the diagnosis code memory, check the diagnosis code again.
(7) Disconnect the negative battery terminal.
Is the diagnosis code No. B1660 set?
Go to Step 4.
Replace the rear seat belt pre-tensioner (LH) (Refer to ).
 
STEP 4. Resistance measurement at the SRS-ECU connector and the rear seat belt pre-tensioner (LH) connector.
(1) Check that the negative battery terminal is disconnected. If the negative battery terminal is connected, disconnect it.
(2) Disconnect the SRS-ECU connector.
 
(3)
dangerTo release the SRS-ECU connector short spring in the following operations, disconnect this seat belt pre-tensioner connector, and keep the squib circuit shorted.
Use the flat-tipped screwdriver to pull out the locking button of harness side connector. After releasing the lock, disconnect the rear seat belt pre-tensioner (LH) harness side connector.
 
(4)
cautionThe short spring may not be released due to the insufficient insertion. Therefore, insert the insulator for 4 mm or more.
Insert an insulator (width: 3 mm, thickness: 0.5 mm) such as cable tie between the RPL-, RPL+ line the short spring, and release the short spring.

 
(5) Connect special tool resistor harness (MB991884) to the removed rear seat belt pre-tensioner (LH) harness side connector.
 
(6) Take the measurements below at the resistor harness and SRS-ECU harness side connector.
  • Continuity RPL- line between SRS-ECU connector and resistor harness connector
  • Continuity RPL+ line between SRS-ECU connector and resistor harness connector
OK: Continuity (less than 2 Ω)
Is the check result normal?
Go to Step 5.
Repair the wiring harness RPL-, RPL+ line between the SRS-ECU connector and the rear seat belt pre-tensioner (LH) connector.
 
STEP 5. Check whether the diagnosis code is set again.
Is the diagnosis code No. B1660 set?
Replace SRS-ECU (Refer to ).
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).