• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Air Suspension Compressor Assembly Battery Positive Voltage | 1, 2, 4, 6 | 1, 2, 4, 6 | -- | -- |
Air Suspension Compressor Assembly Ignition 3 Voltage | 1, 2, 4, 6 | 1, 2, 4, 6 | -- | -- |
Air Suspension Compressor Assembly Ground | -- | 1, 2, 4, 6 | -- | -- |
Air Suspension Inflator Switch Ground | -- | 4, 6 | -- | -- |
Air Suspension Inflator Switch Indicator Control | 4 | 4 | 3 | -- |
Air Suspension Inflator Switch Signal | 5 | 6 | 6 | -- |
Left Rear Air Suspension Sensor Low Reference | -- | DTC 002 | -- | -- |
Left Rear Air Suspension Sensor Signal | DTC 002 | DTC 002 | DTC 002 | -- |
Right Rear Air Suspension Sensor Low Reference | -- | DTC 003 | -- | -- |
Right Rear Air Suspension Sensor Signal | DTC 003 | DTC 003 | DTC 003 | -- |
Vehicle Speed Signal | B0540 | 7 | B0540 | -- |
1. Air Springs Do Not Deflate 2. Air Springs Do Not Inflate 3. Air Suspension Inflator Switch Indicator Always ON 4. Air Suspension Inflator Switch Indicator Inoperative 5. Inflator Always ON 6. Inflator Inoperative 7. Inflator Will Operate While Vehicle is in Motion |
The left rear air suspension sensor arm is attached to an armature that rotates inside a coil. The air suspension compressor assembly determines the angle of the sensor arm by measuring the voltage of the left rear air suspension sensor signal at 50 ms intervals via the left rear air suspension sensor signal circuit.
• | Battery voltage is between 9-16 volts. |
• | The ignition is ON for 30 seconds. |
The air suspension compressor assembly detects a invalid height sensor signal.
• | The air suspension compressor assembly shall disregard the left rear air suspension sensor input and use the right rear air suspension sensor to determine the vehicle height. |
• | If both air suspension sensor DTCs are set, the air suspension compressor assembly shall deactivate the compressor, corner solenoids, and exhaust solenoids. All leveling functions will be disabled. Inflator functions will not be disabled. |
The DTC will automatically clear when the condition for setting the DTC is removed.
Air Suspension Description and Operation
Ignition ON, load the vehicle with additional weight in the rear. The air suspension compressor should activate raising the vehicle to the calibrated vehicle level. Remove the additional load and the compressor will exhaust the necessary amount of air to return to the calibrated vehicle level.
⇒ | If greater than the specified value, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the air suspension compressor assembly. |
⇒ | If the sensor fails the component test, replace the sensor |
⇒ | If the circuit tests normal, replace the air suspension compressor assembly. |
⇒ | If not within the specified range or if the reading is erratic, replace the sensor. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.