TRW SRS Unit

Control System DTCs

SRS DTC Troubleshooting: 45-1x - TRW SRS unit

DTC 45-1x ("x" can be 0 thru 9 or A thru F) : No Signal From the Left Side Impact Sensor (second) (TRW SRS unit)

NOTE:
* Before doing this troubleshooting procedure, find out if the vehicle was in a collision. If so, verify that all the required components were replaced with new components, of the correct part number, and that they were properly installed Service and Repair.
* Before doing this troubleshooting procedure, review SRS Precautions and Procedures Service and Repair, General Troubleshooting Information Reading and Clearing Diagnostic Trouble Codes, and Battery Terminal Disconnection and Reconnection Procedures.
* Before replacing the SRS unit, check the SRS unit software version with the HDS. If the software version is not the latest, update the SRS unit software Programming and Relearning, and retest.

1. System check:

System check
-1. Turn the ignition switch to LOCK (0).

-2. Connect the HDS to the data link connector (DLC) Reading and Clearing Diagnostic Trouble Codes.

-3. Turn the ignition switch to ON (II).

-4. From the HDS Main Menu, select SRS, then Data List. Read "ECU MAKER" displayed on the HDS.

Is TRW indicated?
-YES- Go to step 2.
-NO- Troubleshoot appropriate DTC.
CONTINENTAL SRS unit:
*DTC 45-1x Continental SRS Unit
DENSO SRS unit:
*DTC 45-1x Denso SRS Unit

2. DTC check:

DTC check
-1. Clear the DTCs with the HDS Reading and Clearing Diagnostic Trouble Codes.

-2. Turn the ignition switch to ON (II), then wait for 10 seconds.

-3. Check for DTCs with the HDS Reading and Clearing Diagnostic Trouble Codes.

Are DTCs indicated?
-Only DTC 45-11- Go to step 3.
-DTC 45-1x (except 45-11)- Faulty left side impact sensor (second); replace the left side impact sensor (second) Side Impact Sensor (Second) Removal and Installation (4-door), then clear the DTC.
-NO DTC- Intermittent failure, the system is OK at this time. Go to Troubleshooting Intermittent Failures Reading and Clearing Diagnostic Trouble Codes. If another DTC is indicated, troubleshoot the DTC.

3. Shorted wire check (LS2+ line to LS2- line):

Shorted wire check (LS2+ line to LS2- line)
-1. Turn the ignition switch to LOCK (0).

-2. Disconnect the negative cable from the battery, then wait at least 3 minutes.

-3. Disconnect the following connectors.





-4. Measure the resistance between test points 1 and 2.









Is there an open circuit, or at least 1 MOhms?
-YES- Go to step 4.
-NO- Short to another wire in the floor wire harness between the left side impact sensor (first) and the left side impact sensor (second); replace the floor wire harness, then clear the DTC.

4. Shorted wire check (LS2+, LS2- lines):

Shorted wire check (LS2+, LS2- lines)
-1. Measure the resistance between test points 1 and 2.














Is there an open circuit, or at least 1 MOhms?
-YES- Go to step 5.
-NO- Short to ground in the floor wire harness between the left side impact sensor (first) and the left side impact sensor (second); replace the floor wire harness, then clear the DTC.

5. Shorted wire check (LS2+, LS2- lines to power):

Shorted wire check (LS2+, LS2- lines to power)
-1. Reconnect the negative cable to the battery.

-2. Turn the ignition switch to ON (II).

-3. Measure the voltage between test points 1 and 2.














Is there less than 0.2 V?
-YES- Go to step 6.
-NO- Short to power in the floor wire harness between the left side impact sensor (first) and the left side impact sensor (second); replace the floor wire harness, then clear the DTC.

6. Open wire check (LS2+, LS2- lines):

Open wire check (LS2+, LS2- lines)
-1. Turn the ignition switch to LOCK (0).

-2. Connect the red terminal (A) of SRS simulator lead L to the SRS inflator simulator (jumper connector), then connect SRS simulator lead L to the left side impact sensor (first) 4P connector (B) on the floor wire harness.





-3. Measure the resistance between test points 1 and 2.









Is there less than 1.0 Ohms?
-YES- Faulty left side impact sensor (second) or SRS unit; replace the left side impact sensor (second) Side Impact Sensor (Second) Removal and Installation (4-door), then clear the DTC, and retest. If the DTC is still present, replace the SRS unit Service and Repair.
-NO- Open in the floor wire harness between the left side impact sensor (first) and the left side impact sensor (second); replace the floor wire harness, then clear the DTC.