DTC B0086 or B0087
Diagnostic Instructions
DTC Descriptors
DTC B0086 02: Right Front Side Impact Sensor Short to Ground
DTC B0086 05: Right Front Side Impact Sensor High Voltage/Open
DTC B0086 39: Right Front Side Impact Sensor Internal Malfunction
DTC B0086 3A: Right Front Side Impact Sensor Incorrect Component Installed
DTC B0086 71: Right Front Side Impact Sensor Invalid Data
DTC B0087 02: Left Rear Side Impact Sensor Short to Ground
DTC B0087 05: Left Rear Side Impact Sensor High Voltage/Open
DTC B0087 39: Left Rear Side Impact Sensor Internal Malfunction
DTC B0087 3A: Left Rear Side Impact Sensor Incorrect Component Installed
DTC B0087 71: Left Rear Side Impact Sensor Invalid Data
Diagnostic Fault Information
Circuit
| Short to Ground
| Open/High Resistance
| Short to Voltage
| Signal Performance
|
Right Front Side Impact Sensor High Signal
| B0086 02, B0087 02
| B0086 05
| B0086 05, B0087 05
| B0086 39
|
Right Front Side Impact Sensor Low Reference
| B0086 02, B0087 02
| B0086 05
| B0086 05, B0087 05
| B0086 39
|
Left Rear Side Impact Sensor High Signal
| B0086 02, B0087 02
| B0087 05
| B0086 05, B0087 05
| B0087 39
|
Left Rear Side Impact Sensor Low Reference
| B0086 02, B0087 02
| B0087 05
| B0086 05, B0087 05
| B0087 39
|
Circuit/System Description
The impact sensors are equipped on vehicles to supplement the supplemental inflatable restraint (SIR) system performance. The impact sensors are electronic and are not part of the deployment loops, but instead provide inputs to the sensing and diagnostic module (SDM). The impact sensors can assist in determining the severity of some frontal and side collisions. The SDM uses the input from the impact sensors to assist in determining the severity of a collision further supporting air bag deployment. If the SDM determines a deployment is warranted, the SDM will cause current to flow through the deployment loops deploying the air bags.
Conditions for Running the DTC
Ignition voltage is between 9-16 V.
Conditions for Setting the DTC
Any of the following conditions exist for 10 seconds:
B0086 02, B0087 02
• | The sensor has been shorted to ground. |
• | The sensor current is greater than 23 mA for greater than 5 milliseconds. |
B0086 05, B0087 05
• | The sensor circuit is open. |
• | The SDM has not received a message from the sensor for greater than 375 milliseconds. |
B0086 39, B0087 39
• | The SDM has received a Not OK message from the sensor. |
• | The SDM has not received a message. |
B0086 3A, B0087 3A
• | The SDM has received identification message from the sensor, which does not match the identification stored in the SDM memory. |
• | The SDM has reset the impact sensor twice without detecting the correct identification message. |
B0086 71, B0087 71
The SDM has received invalid serial data from the sensor.
Action Taken When the DTC Sets
The SDM requests the instrument panel cluster to illuminate the AIR BAG indicator.
Conditions for Clearing the DTC
• | The condition for setting the DTC no longer exists. |
• | A history DTC will clear once 100 malfunction-free ignition cycles have occurred. |
• | An ignition cycle is required for the DTC to go from current to history. |
Reference Information
Schematic Reference
SIR Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
SIR System Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
Note: Refer to SIR Service Precautions .
Inspect all terminals for damage or corrosion when disconnecting connectors. Damage or corrosion in the following requires repair or replacement of the affected component/connector.
• | Front impact sensor wiring harness connector |
• | Side impact sensor wiring harness connector |
• | SDM wiring harness connector |
Note: The connector and connector position assurance (CPA) may seat independently of each other. Both the connector and CPA should seat with an audible and/or tactile click. The CPA isolates the shorting-bars within the connector allowing the deployment circuit to operate properly. Replace any CPA that is damaged or missing.
If the condition is intermittent or cannot be duplicated, disconnect the connectors and add Nyogel lubricant 760G. This procedure will correct the high resistance condition due to terminal fretting corrosion.
- Verify that DTC B0086 or B0087 symptom byte 39 or 71 is not set as current.
⇒ | If DTC B0086 or B0087 symptom byte 39 or 71 is set as current
|
| Replace the sensor listed below: |
• | B0086 - B63LF side impact sensor-right front |
• | B0087 - B63RR side impact sensor-left rear |
⇓ | If DTC B0086 or B0087 symptom byte 39 or 71 is not set as current
|
- Verify that DTC B0086 or B0087 symptom byte 3A is not set as current.
⇒ | If DTC B0086 or B0087 symptom byte 3A is set as current
|
| Replace the incorrect B63 side impact sensor |
⇓ | If DTC B0086 or B0087 symptom byte 3A is not set as current
|
- Verify that DTC B0086 or B0087 symptom byte 02 or 05 is set as current.
⇒ | If only DTC B0086 symptom byte 02 or 05 is set as current
|
| Refer to Circuit/System Testing - Only DTC B0086 or B0087 is set. |
⇒ | If only DTC B0087 symptom byte 02 or 05 is set as current
|
| Refer to Circuit/System Testing - Only DTC B0086 or B0087 is set. |
⇒ | If both DTC B0086 or B0087 symptom byte 02 or 05 is set as current
|
| Refer to Circuit/System Testing - Both DTC B0086 and B0087 are set. |
⇓ | If DTC B0086 or B0087 symptom byte 02 or 05 is not set as current
|
- All OK.
Circuit/System Testing
Note: The signal circuit is shared at the K36 SDM between the B63RF side impact sensor right front and the B63LR side impact sensor left rear (DTC B0086 and DTC B0087). Therefore a short to ground or short to voltage in either of these signal circuits can set a DTC for both circuits, and an open in either circuit should only set its corresponding DTC.
Only DTC B0086 or B0087 is set
- Vehicle OFF, disconnect the harness connector at the appropriate B63 side impact sensor. It may take up to 2 minutes for all vehicle systems to power down.
- Test for less than 10 Ω between the low reference circuit terminal 2 and ground.
2.1. | Disconnect the X2 harness connector at the K36 SDM. |
2.2. | Test for less than 2 Ω in the low reference circuit end to end. |
⇒ | If 2 Ω or greater, repair the open/high resistance in the circuit. |
⇒ | If less than 2 Ω, replace the K36 SDM. |
- Disconnect the X2 harness connector at the K36 SDM.
- Test for less than 2 Ω between the signal circuit terminal 1 at the B63 side impact sensor and the K36 SDM terminal listed below:
• | Right front signal terminal 22 X2 |
• | Left rear signal terminal 27 X2 |
| Repair the open/high resistance in the circuit. |
- Verify that the K36 SDM calibrations match the VIN data, software part number, and calibration part number.
⇒ | If the K36 SDM calibrations do not match the VIN data |
⇓ | If the K36 SDM calibrations match the VIN data |
- Replace the B63 side impact sensor.
- Verify the DTC does not set.
⇓ | If the DTC does not set
|
- All OK
Both DTC B0086 and B0087 are set
- Vehicle OFF. Disconnect the X2 harness connector at the K36 SDM. It may take up to 2 minutes for all vehicle systems to power down.
- Test for greater than 50k Ω between each signal circuit listed below and ground:
• | Right front signal circuit - terminal 22 X2 |
• | Left rear signal circuit - terminal 27 X2 |
2.1. | Disconnect the harness connector at the B63 side impact sensor that failed the test. |
2.2. | Test for infinite resistance between the signal circuit and ground. |
⇒ | If less than infinite resistance, repair the short to ground on the circuit. |
⇒ | If infinite resistance, replace the B63 side impact sensor. |
- Test for less than 1 V between the signal circuit terminals listed below and ground:
• | Right front signal circuit - terminal 22 X2 |
• | Left rear signal circuit - terminal 27 X2 |
3.1. | Disconnect the harness connector at the B63 side impact sensor that failed the test. |
3.2. | Test for less than 1 V between signal circuit and ground. |
⇒ | If 1 V or greater, repair the short to voltage in the circuit. |
⇒ | If less than 1 V, replace the B63 side impact sensor. |
- Verify that the K36 SDM calibrations match the VIN data, software part number, and calibration part number.
⇒ | If the K36 SDM calibrations do not match the VIN data |
⇓ | If the K36 SDM calibrations match the VIN data |
- Replace the K36 SDM.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair.
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