Reading and Clearing Diagnostic Trouble Codes
How to Troubleshoot the SRS
DTC (Diagnostic Trouble Codes)
The self-diagnostic function of the SRS system allows it to locate the causes of system problems and then store this information in memory. For easier troubleshooting, this data can be retrieved via a data link circuit.
- When you turn the ignition switch to ON (II), the SRS indicator comes on. If it goes off after 6 seconds, the system is normal, and is not currently detecting any abnormality.
- If there is an abnormality, the system locates and defines the problem, stores this information in memory, and turns the SRS indicator on. The data remains in memory even when the ignition switch is turned to LOCK (0) or if the battery is disconnected.
- The data is stored in memory as a diagnostic trouble code (DTC).
- DTCs are either latching or resetting depending on the malfunction. With resetting DTCs, the SRS indicator goes off the next time the ignition switch is turned to ON (II) and the system is normal, but the DTC is still stored. With latching DTCs, the SRS indicator does not turn OFF until the malfunction is repaired and the DTC is cleared.
- When you connect the HDS to the data link connector (DLC), you can retrieve a more detailed DTC in the Honda Systems "SRS" menu.
- After reading and recording the DTC, proceed with the troubleshooting procedure for that code.
Precautions
- Use only a digital multimeter to check the system. If it's not a Honda multimeter, make sure its output is 10 mA (0.01 A) or less when switched to the smallest value in the ohmmeter range. A tester with a higher output could damage the airbag circuit or cause accidental airbag deployment and possible injury.
- Whenever the ignition switch is ON (II), or has been turned OFF for less than 3 minutes, be careful not to bump the SRS unit; the airbags could accidentally deploy and cause damage or injuries.
- Before you remove the dashboard wire harness A or the right side wire harness, disconnect the driver's airbag connector, the front passenger's airbag connector, both side airbag connectors, both side curtain airbag connectors, and both seat belt tensioner connectors.
- Make sure the battery is sufficiently fully charged. If the battery is dead or low, measured values may not be correct.
- Do not touch a tester probe to the terminals in the SRS unit or harness connectors, and do not connect the SRS unit terminals or the sensor terminals with a jumper wire. Use only the backprobe set and the multimeter. Backprobe spring-loaded lock type connectors correctly.
Reading the DTC
1. Make sure the ignition switch is in LOCK (0).
2. Connect the HDS to the data link connector (DLC) (A).
3. Turn the ignition switch to ON (II).
4. Make sure the HDS communicates with the vehicle and the SRS unit. If it does not, troubleshoot the DLC circuit. Testing and Inspection
5. Use the HDS to check for DTCs.
6. Read and record the DTC.
7. Turn the ignition switch to LOCK (0), then wait for 10 seconds.
8. Disconnect the HDS from the DLC.
9. Do the troubleshooting procedure for the DTC.
Clear the DTC Memory with the HDS
NOTE: Make sure the battery is fully charged before you begin.
1. Make sure the ignition switch is in LOCK (0).
2. Connect the HDS to the data link connector (DLC) (A).
3. Turn the ignition switch to ON (II).
4. Make sure the HDS communicates with the vehicle and the SRS unit. If it does not, troubleshoot the DLC circuit. Testing and Inspection
5. In the SRS MENU of the HDS, select SRS, then DTC to clear the DTC(s).
6. Turn the ignition switch to LOCK (0), then wait for 10 seconds.
7. Disconnect the HDS from the DLC.
Clear the DTC Memory Using MES Connector without the HDS
Special Tools Required
- SCS Service Connector 07PAZ-001010A
NOTE: Make sure the battery is fully charged before you begin.
To clear the DTC(s) from the SRS unit, use the HDS or the following procedure.
1. Make sure the ignition switch is in LOCK (0).
2. Connect the SCS service connector (A) to the yellow MES 2P connector (B). Do not use a jumper wire.
3. Turn the ignition to switch to ON (II).
4. The SRS indicator will come on for about 6 seconds, and then go off. Remove the SCS service connector from the MES connector (2P) within 4 seconds after the indicator goes off.
5. The SRS indicator will come on again. Reconnect the SCS service connector to the MES connector (2P) within 4 seconds after the indicator comes on.
6. When the SRS indicator goes off, remove the SCS service connector from the MES connector (2P) within 4 seconds.
7. The SRS indicator blinks two times, indicating that the memory has been cleared.
8. Turn the ignition switch to LOCK (0), and wait for 10 seconds.
9. Turn the ignition switch to ON (II) again. If the SRS indicator comes on for about 6 seconds, and then goes off, the system is OK.
Troubleshooting Intermittent Failures
If there was a malfunction that sets a DTC, but it does not recur, it will be stored in the memory as an intermittent failure, and the SRS indicator may come on depending on the malfunction detected.
NOTE:
- Check the condition of the battery, Testing and Inspection and the charging system. Charging System Indicator Circuit Troubleshooting Low battery voltage may cause some intermittent failures.
- A faulty cable reel can cause intermittent connections related to the driver's airbag inflator DTCs.
After checking the DTC, troubleshoot as follows:
1. Read the DTC (see Reading the DTC).
2. Clear the DTC memory (see Clear the DTC Memory).
3. Set the parking brake, then start the engine, and let it idle.
4. The SRS indicator comes on for about 6 seconds and then goes off.
5. Shake the related wire harnesses and the connectors, and look for loose connections, poor pinfits, and poor grounds.
6. Take a test-drive (quick acceleration, quick braking, and cornering), turn the steering wheel fully left and right, and hold it there for 5 to 10 seconds. If the problem recurs, the SRS indicator will come on.
7. If you cannot duplicate the concern, ask the customer about the conditions when it occurred, or ask the customer to demonstrate the concern.
8. If you cannot duplicate the intermittent failure, the system is OK at this time.
Checking Seat Weight Sensors After a Vehicle Collision
1. Position the front passenger's seat to the rear most position, adjust the seat-back to the forward most position. Do not move the seat from this position.
2. Drive the vehicle, accelerate to 20 mph (36 km/h), then stop on level ground.
3. Make sure the ignition switch is in LOCK (0).
4. Connect the HDS to the data link connector (DLC) (A).
5. Turn the ignition switch to ON (II).
6. From the SRS inspection menu, select Seat Weight Sensor, then Misc test, then SEAT OUTPUT CHK and follow the prompts until the ODS operation check has been completed.
