Manufacturer Code Charts: 30
Adaptive Cruise Control (ACC) DTC Troubleshooting: 30
DTC 30: Adaptive Cruise Control (ACC) Relay Circuit Malfunction
1. Check the brake lights without pressing the brake pedal.
Are the brake lights off?
YES - Go to step 10.
NO - Go to step 2.
2. Check the brake pedal height and adjust it. Brake Pedal and Brake Pedal Position Switch Adjustment
3. Check the brake lights without pressing the brake pedal.
Are the brake lights off?
YES - Intermittent failure, the system is OK at this time. Check for loose or poor connections.
NO - Go to step 4.
4. Test the brake pedal position switch. Brake Pedal Position Switch Test
Is the brake pedal position switch OK?
YES - Go to step 5.
NO - Adjust or replace the brake pedal position switch and recheck. Service and Repair
5. Test the ACC relay. Power Relay Test
Is the relay OK?
YES - Go to step 6.
NO - Replace the relay and recheck.
6. Disconnect the brake pedal position switch 4P connector.
7. Measure the voltage between brake pedal position switch 4P connector terminal No. 2 and body ground.
Is there battery voltage?
YES - Repair a short to power in the wire.
NO - Go to step 8.
8. Disconnect the ACC unit 20P connector.
9. Measure the voltage between ACC unit 20P connector terminal No. 1 and body ground.
Is there battery voltage?
YES - Repair a short to power in the wire between the ACC unit and the ACC relay, or between the ACC unit and the brake lights circuits.
NO - Check for loose or poor connections. If OK, replace the ACC unit. Service and Repair
10. Clear the DTCs with the HDS.
11. Turn the ACC switch ON.
12. Check the brake lights with the brake pedal pressed.
Do the brake lights come on?
YES - Go to step 13.
NO - Go to step 37.
13. Check for DTCs with the HDS.
Is DTC 30 indicated?
YES - Go to step 14
NO - Go to step 20.
14. Turn the ignition switch to LOCK (0).
15. Remove the ACC relay.
16. Disconnect the ACC unit 20P connector.
17. Disconnect the brake pedal position switch 4P connector.
18. Check for continuity between the ACC unit 20P connector No. 1 terminal and body ground.
Is there continuity?
YES - Repair a short to ground in the wire between the ACC unit and the ACC relay.
NO - Go to step 19.
19. Check for continuity between ACC unit 20P connector terminal No. 1 and ACC relay 5P connector terminal No. 1.
Is there continuity?
YES - Check for loose or poor connections. If OK, replace the ACC unit. Service and Repair
NO - Repair an open in the wire between the ACC unit and the ACC relay.
20. Test the ACC relay. Power Relay Test
Is the relay OK?
YES - Go to step 21.
NO - Replace the relay and recheck.
21. Remove the ACC relay.
22. Measure the voltage between ACC relay 5P connector terminal No. 2 and body ground.
Is there battery voltage?
YES - Go to step 23.
NO - Repair an open in the wire between the No. 13 (15 A) fuse in the under-hood fuse/relay box and the ACC relay.
23. Turn the ignition switch to ON (II).
24. Measure the voltage between ACC relay 5P connector terminal No. 5 and body ground.
Is there battery voltage?
YES - Go to step 25.
NO - Repair an open in the wire between the No. 29 (7.5 A) fuse in the under-dash fuse/relay box and the ACC relay.
25. Turn the ignition switch to LOCK (0).
26. Disconnect the ACC unit 20P connector.
27. Check for continuity between ACC unit 20P connector terminal No. 16 and body ground.
Is there continuity?
YES - Repair a short to ground in the wire between the ACC unit and the ACC relay.
NO - Go to step 28.
28. Check for continuity between ACC unit 20P connector terminal No. 16 and ACC relay 5P connector terminal No. 3.
Is there continuity?
YES - Go to step 29.
NO - Repair an open in the wire between the ACC unit and the ACC relay.
29. Install the ACC relay.
30. Reconnect the ACC unit 20P connector.
31. Clear the DTCs with the HDS.
32. Turn the ignition switch to LOCK (0).
33. Turn the ignition switch to ON (II) and the ACC switch ON.
34. Select ADAPTIVE CRUISE CONTROL (ACC) from the DRIVING SUPPORT menu, then enter ACC RELAY from the FUNCTION TEST menu.
35. Do the ACC relay function test with the HDS.
36. Check for DTCs with the HDS.
Is DTC 30 indicated?
YES - Check for loose or poor connections. If OK, replace the ACC unit. Service and Repair
NO - Troubleshoot the indicated DTC(s). If there are no DTCs, the system is OK at this time.
37. Check for the DTCs with the HDS.
Is DTC 30 indicated?
YES - Go to step 38.
NO - Go to step 44.
38. Test the ACC relay. Power Relay Test
Is the relay OK?
YES - Go to step 39.
NO - Replace the relay and recheck.
39. Remove the ACC relay.
40. Disconnect the ACC unit 20P connector.
41. Disconnect each the brake light 3P connector and the high mount brake light 3P connector.
42. Check for continuity between ACC unit 20P connector terminal No. 1 and body ground.
Is there continuity?
YES - Repair a short to ground in the wire between the ACC unit and the ACC relay.
NO - Go to step 43.
43. Check for continuity between ACC unit 20P connector terminal No. 1 and ACC relay 5P connector terminal No. 1.
Is there continuity?
YES - Check for loose or poor connections. If OK, replace the ACC unit. Service and Repair
NO - Repair an open in the wire between the ACC unit and the ACC relay.
44. Check the brake lights with the brake pedal pressed.
Do the brake light come on?
YES - Intermittent failure, the system is OK at this time. Check for loose or poor connections.
NO - Go to step 45.
45. Check the brake pedal height and adjust it. Brake Pedal and Brake Pedal Position Switch Adjustment
46. Test the brake pedal position switch. Brake Pedal Position Switch Test
47. Check the brake lights with the brake pedal pressed.
Do the brake lights come on?
YES - Intermittent failure, the system is OK at this time. Check for loose or poor connections.
NO - Repair an open in the BLK wire or poor ground (G701). Rear Shelf Wire Harness, Rear Wire Harness And Rear Window Defogger Ground Wire Connector And Harness Locations