Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Automatic Level Control Schematics | |||
1 | Did you review the Automatic Level Control System Description and Operation and perform the necessary inspections? | Go to Step 2 | |
2 |
Does the automatic level control (ALC) air compressor operate? | Go to Step 3 | Go to Step 4 |
3 | Does the rear of the vehicle rise and not leak down? | System OK | |
4 |
Does the test lamp illuminate? | Go to Step 5 | Go to Step 14 |
5 | Connect a test lamp between the ALC height sensor circuit and the ALC sensor ground circuit. Does the test lamp illuminate? | Go to Step 6 | Go to Step 15 |
6 | Connect a test lamp between the ALC relay coil supply voltage circuit and a good ground. Does the test lamp illuminate? | Go to Step 7 | Go to Step 8 |
7 | Connect a 10 amp fused jumper wire between the ALC relay coil supply voltage circuit and a good ground. Does the ALC air compressor activate? | Go to Step 20 | Go to Step 10 |
8 | Probe the ALC relay coil supply voltage circuit of the ALC relay connector with a test lamp connected to a good ground. Does the test lamp illuminate? | Go to Step 16 | Go to Step 9 |
9 | Probe the accessory voltage circuit of the ALC relay connector with a test lamp connected to a good ground. Does the test lamp illuminate? | Go to Step 21 | Go to Step 17 |
10 |
Does the ALC air compressor activate? | Go to Step 21 | Go to Step 11 |
11 |
Does the test lamp illuminate? | Go to Step 12 | Go to Step 19 |
12 | Connect a test lamp between the battery positive voltage circuit and the ground circuit of the ALC air compressor connector. Does the test lamp illuminate? | Go to Step 13 | Go to Step 18 |
13 | Test the ALC compressor harness for a poor connection or an open. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs or Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 23 | Go to Step 22 |
14 | Repair the open in the battery positive voltage circuit to the ALC sensor. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 23 | -- |
15 | Repair the open in the ALC sensor ground circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 23 | -- |
16 | Repair the open in the ALC relay coil supply voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 23 | -- |
17 | Repair the open in the accessory voltage circuit to the ALC relay. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 23 | -- |
18 | Repair the open in the ALC air compressor ground circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 23 | -- |
19 | Repair the open in the battery positive voltage circuit of the ALC air compressor. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 23 | -- |
20 | Replace the ALC sensor. Refer to Automatic Level Control Sensor Replacement . Did you complete the replacement? | Go to Step 23 | -- |
21 | Replace the ALC air compressor relay. Refer to Automatic Level Control Relay Replacement . Did you complete the replacement? | Go to Step 23 | -- |
22 | Replace the ALC air compressor. Refer to Air Compressor Replacement . Did you complete the replacement? | Go to Step 23 | -- |
23 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 3 |
