For 1990-2009 cars

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 |

1. Disconnect the auto level control air inflator relay connector and the auto level control air compressor connector.
2. Replace ELC/TRAILER and/or PWR QTR VENT fuse if it is blown.
3. Turn the ignition switch to the ON position.
4. Using a test light, frontprobe the auto level control air compressor harness connector from terminal A. terminal C, and terminal E to ground. Frontprobe auto level control air inflator relay harness connector from terminal D to ground.

Does the test light come on in all four checks?

--

Go to Step 3

Go to Step 2

2 |

1. Repair a short to ground in CKT 1240 or CKT 743.
2. Replace ELC/TRAILER and/or PWR QTR VENT fuse if necessary.
3. Perform system check to verify fuse no longer shorts out under same conditions. Refer to Automatic Level Control System Operation Check .

Has the repair been made and the system rechecked?

--

System OK

--

3 |

1. Disconnect the auto level control air inflator relay and the auto level control sensor harness connectors.
2. Using a test light, backprobe from B+ to the auto level control air inflator relay harness connector terminal B and terminal C.

Is the test light on?

--

Go to Step 12

Go to Step 4

4 | Reconnect the auto level control air compressor harness connector. Is the ELC/TRAILER and/or PWR QTR VENT fuse blown? | -- | Go to Step 8 | Go to Step 5
5 |

1. Reconnect the auto level control air inflator relay, auto level control sensor, and the auto level control air solenoid valve harness connectors.
2. Replace ELC/TRAILER and/or PWR QTR VENT fuse if necessary.
3. Load rear of passenger compartment with 181 kg (400 lbs), enough to activate compressor.
4. Turn vehicle ignition to RUN.
5. Listen closely to auto level control air compressor for 1 minute.

Is the ELC/TRAILER and/or PWR QTR VENT fuse OK and does the solenoid click after approximately 40 seconds?

--

Go to Step 7

Go to Step 6

6 |

1. Disconnect the auto level control air compressor harness connector.
2. While listening closely to auto level control air inflator solenoid, connect a 20 A fused jumper to the auto level control air compressor harness connector from terminal B to ground and from B+ to terminal C.

Does solenoid click and are the fuses in jumpers OK?

--

Go to Step 9

Go to Step 7

7 |

1. Replace the auto level control air compressor head. Refer to Automatic Level Control Air Compressor Head Replacement .
2. Reconnect the auto level control air compressor harness connector.
3. Replace ELC/TRAILER and/or PWR QTR VENT fuse if necessary.
4. Perform system check to verify fuse no longer blows under same conditions. Refer to Automatic Level Control System Operation Check .

Is the ELC/TRAILER and/or PWR QTR VENT fuse blown?

--

Go to Step 8

System OK

8 |

1. Replace auto level control air compressor. Refer to Air Compressor Replacement .
2. Replace fuse if necessary.
3. Perform system check to verify fuse no longer blows under same conditions. Refer to Automatic Level Control System Operation Check .

Is the ELC/TRAILER and/or PWR QTR VENT fuse blown?

--

Go to Step 9

System OK

9 |

1. Replace auto level control air inflator relay. Refer to Automatic Level Control Relay Replacement .
2. Replace the ELC/TRAILER and/or PWR QTR VENT fuse if necessary.
3. Perform system check to verify fuse no longer blows under same conditions. Refer to Automatic Level Control System Operation Check .

Is the ELC/TRAILER and/or PWR QTR VENT fuse blown?

--

Go to Step 11

System OK

10 |

1. Replace auto level control air compressor. Refer to Air Compressor Replacement .
2. Replace the ELC/TRAILER and/or PWR QTR VENT fuse if necessary.
3. Perform system check to verify fuse no longer blows under same conditions. Refer to Automatic Level Control System Operation Check .

Is the ELC/TRAILER and/or PWR QTR VENT fuse blown?

--

Go to Step 10

System OK

11 |

1. Replace auto level control sensor. Refer to Automatic Level Control Sensor Replacement .
2. Replace the ELC/TRAILER and/or PWR QTR VENT fuse if necessary.
3. Perform system check to verify fuse no longer blows under same conditions. Refer to Automatic Level Control System Operation Check .

Is the ELC/TRAILER and/or PWR QTR VENT fuse blown?

--

Go to Step 8

System OK

12 |

1. Replace auto level control air inflator solenoid valve. Refer to Inflator Solenoid Replacement .
2. Replace the ELC/TRAILER and/or PWR QTR VENT fuse if necessary.
3. Perform system check to verify fuse no longer blows under same conditions. Refer to Automatic Level Control System Operation Check .

Is the ELC/TRAILER and/or PWR QTR VENT fuse blown?

--

Go to Step 13

System OK

13 | Check for a short to ground in CKT 1248. Is there a short to ground in CKT 1248? | -- | Go to Step 14 | Go to Step 15
14 | Repair a short to ground in either CKT 1248. Has the repair been made and the system rechecked? | -- | System OK | --
15 | Check for a short to ground in CKT 1249. Is there a short to ground in CKT 1249? | -- | Go to Step 16 | Go to Step 17
16 | Repair a short to ground in CKT 1249. Has the repair been made and the system rechecked? | -- | System OK | --
17 | Check for a short to ground in CKT 1240. Is there a short to ground in CKT 1240? | -- | Go to Step 18 | System OK
18 | Repair a short to ground in CKT 1240. Has the repair been made and the system rechecked? | -- | System OK | --