U0176
U0176-LOST COMMUNICATION WITH RIGHT SIDE SATELLITE ACCELERATION SENSOR 2
Special Tools:
For a complete wiring diagram, refer to the Wiring Information.
Theory of Operation
The location of the right side impact sensor 2 is in the C-pillar area just past the second row seating. Impact sensors perform their own self test using power supplied by the Occupant Restraint Controller (ORC) then communicate this status back to the ORC. The repair of this fault centers on verifying the integrity of the sensor's internal circuitry and software validity. If the scan tool shows this DTC has a Stored history of setting then the right side impact sensor is to be replaced. A short to voltage fault on the right side impact sensor 1 sensor wiring can cause a loss of comm impact sensor 2 code to set and the possible replacement of a good right side impact sensor 2. The right side impact 1, and 2 sensors are wired in a daisy chain pattern. The short to battery fault in a loss of comm or internal circuit failure of the side impact sensor 1 can cause the impact sensor 2 on the same side to set a loss of comm code.
- When Monitored:
The Occupant Restraint Controller (ORC) continuously communicates with the Right Side Impact Sensor 2 over the sensor signal circuit. The sensor communication and on board diagnostics are powered by the ORC signal.
- Set Condition:
This code will set, if the ORC and the Right Side Impact Sensor 2 do not establish and maintain valid data communications.
1. VERIFY THAT DTC U0176-LOST COMMUNICATION W/RIGHT SIDE SATELLITE ACCELERATION SENSOR 2
WARNING: Turn the ignition off disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
NOTE: Using the wiring diagram/schematic as a guide check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.
NOTE: If after the harness inspection it appears the impact sensor connector is only seated halfway. Reseat the harness connector into the impact sensor and lock the tab.
WARNING: Turn the ignition on, then reconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
1. Turn the ignition on.
2. With the scan tool, read ORC DTCs.
NOTE: Make sure the battery is fully charged.
Does the scan tool display active: B1B75-RIGHT SIDE SATELLITE ACCELERATION SENSOR 1 INTERNAL, U0175-LOST COMMUNICATION W/RIGHT SIDE SATELLITE ACCELERATION SENSOR 1, U0176-LOST COMMUNICATION W/RIGHT SIDE SATELLITE ACCELERATION SENSOR 2?
Yes
- NOTE: Check for active codes and repair for the fault starting with the Internal failure code or codes, check for active or stored status. Upon fixing the right side impact sensor 1 then check the right side impact sensor 2 internal fault if status changes to stored for all codes fault is fixed if status is still active proceed to the right side impact sensor 1 loss of communication code, check for status of the right side impact sensor 1 code status being active. If all codes go to stored status, fault in daisy chain is fixed if code status is still active continue. Check the right side impact sensor 2 for status of the right side impact sensor 2 code going to stored. If status of all codes goes to stored status, fault in daisy chain is fixed if code status is still active continue and fix the fault.
- Check for all other internal and lost communication codes indicated in the right side impact sensor daisy chain wiring before diagnosing DTC U0176-LOST COMMUNICATION W/RIGHT SIDE SATELLITE ACCELERATION SENSOR 2. Go To The DTC Displayed Testing and Inspection. If internal fault 1 and lost comm fault 1 have been checked follow DTC U0176-LOST COMMUNICATION W/RIGHT SIDE SATELLITE ACCELERATION SENSOR 2. Go To 2
No
- Perform the AIRBAG SYSTEM INTERMITTENT TEST. Initial Inspection and Diagnostic Overview.
2. CHECK THE (R18) AND (R20) RIGHT SIDE IMPACT SENSOR 2 SIGNAL AND GROUND CIRCUITS FOR A SHORT TO BATTERY
WARNING: Turn the ignition off, disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
1. Disconnect the Right Side Impact Sensor 2 harness connector.
2. Disconnect the ORC harness connectors.
3. Connect the ORC Adaptor to the ORC harness connector.
WARNING: Turn the ignition on, then reconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
4. Measure the voltage of the (R18) Right Side Impact Sensor 2 Signal circuit and the (R20) Sensor 2 Ground circuit at the Right Side Impact Sensor 2 harness connector.
Is there any voltage present?
Yes
- Repair the (R18) and (R20) Right Side Impact Sensor 2 circuits for a short to battery.
- Perform the AIRBAG SYSTEM VERIFICATION TEST. Airbag System Verification Test.
No
- Go To 3
3. CHECK THE (R18) RIGHT SIDE IMPACT SENSOR 2 SIGNAL CIRCUIT FOR A SHORT TO GROUND
WARNING: Turn the ignition on, then reconnect the battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
1. Measure the resistance between ground and the (R18) Right Side Impact Sensor 2 Signal circuit at the Right Side Impact Sensor 2 harness connector.
Is the resistance below 100K Ohms?
Yes
- Repair the (R18) Right Side Impact Sensor 2 Signal circuit for a short to ground.
- Perform the AIRBAG SYSTEM VERIFICATION TEST. Airbag System Verification Test.
No
- Go To 4
4. CHECK THE (R18) and (R20) RIGHT SIDE IMPACT SENSOR 2 CIRCUITS FOR A SHORT TOGETHER
1. Measure the resistance between the (R18) Right Side Impact Sensor 2 Signal circuit and the (R20) Sensor 2 Ground circuit at the Right Side Impact Sensor 2 harness connector.
Is the resistance below 100K Ohms?
Yes
- Repair the (R18) and (R20) Right Side Impact Sensor 2 circuits shorted together.
- Perform the AIRBAG SYSTEM VERIFICATION TEST. Airbag System Verification Test.
No
- Go To 5
5. CHECK THE (R20) RIGHT SIDE IMPACT SENSOR 2 GROUND CIRCUIT FOR AN OPEN OR HIGH RESISTANCE
1. Measure the resistance of the (R20) Right Side Impact Sensor 2 Ground circuit between the Right Side Impact Sensor 2 harness connector and the Right Side Impact Sensor 1 harness connector.
Is the resistance below 1 Ohm?
Yes
- Go To 6
No
- Repair the (R20) Right Side Impact Sensor 2 Ground circuit for an open or high resistance.
- Perform the AIRBAG SYSTEM VERIFICATION TEST. Airbag System Verification Test.
6. CHECK THE (R18) RIGHT SIDE IMPACT SENSOR 2 CIRCUIT FOR AN OPEN OR HIGH RESISTANCE
1. Measure the resistance of the (R18) Right Side Impact Sensor 2 Signal circuit between the Right Side Impact Sensor 2 harness connector and the SRS Load Tool Adaptor.
Is the resistance below 1 Ohm?
Yes
- Go To 7
No
- Repair the (R18) Right Side Impact Sensor 2 Signal circuit for an open or high resistance.
- Perform the AIRBAG SYSTEM VERIFICATION TEST. Airbag System Verification Test.
7. CHECK OPERATION OF THE RIGHT SIDE IMPACT SENSOR 2
1. Replace the Right Side Impact Sensor 2.
2. Reconnect the vehicle body harness to the impact sensor.
3. Remove any special tools or jumper wires and reconnect all previously disconnected components - except the Battery.
WARNING: Turn the ignition on, then reconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
4. Connect the scan tool to the Data Link Connector - use the most current software available.
5. Use the scan tool and erase the stored codes in all airbag system modules.
6. Turn the Ignition Off, and wait 15 seconds before turning the Ignition On.
7. Wait one minute, and read active codes and if there are none present read the stored codes.
Did the active Right Side Impact Sensor 2 DTC return?
Yes
- Go To 8
No
- Repair is complete.
- Perform the AIRBAG SYSTEM VERIFICATION TEST. Airbag System Verification Test.
8. REPLACE THE OCCUPANT RESTRAINT CONTROLLER
WARNING: Turn the ignition off, disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
WARNING: If the Occupant Restraint Controller (ORC) is dropped at any time, it must be replaced. Failure to take the proper precautions can result in accidental airbag deployment. Failure to follow these instructions may result in possible serious or fatal injury.
If there are no possible causes remaining, view repair.
Repair
- Replace the Occupant Restraint Controller.
- Perform the AIRBAG SYSTEM VERIFICATION TEST. Airbag System Verification Test.