Headlamps Inoperative - Low Beams (w/Leveling (TR7) and HID (TT6))

Step	Action	Yes	No
CAUTION: The high intensity discharge system produces high voltage and current. To reduce the risk of severe shocks and burns: Never open the high intensity discharge system ballast or the arc tube assembly starter. Never probe between the high intensity discharge system ballast output connector and the arc tube assembly. Schematic Reference: Headlights/Daytime Running Lights (DRL) SchematicsConnector End View Reference: Master Electrical Component ListDEFINITION: One or more low beam headlamps inoperative on a vehicle equipped with headlamp leveling with high intensity discharge (HID).
1	Did you perform the Diagnostic System Check - Vehicle?	Go to Step 2	Go to Diagnostic System Check - Vehicle
2	Turn ON the ignition, with the engine OFF. Place the headlamp switch in the ON position. Place the headlamp dimmer switch in the low beam position. Do the low beam headlamps illuminate?	Go to Testing for Intermittent Conditions and Poor Connections	Go to Step 3
3	Are both of the low beam headlamps inoperative?	Go to Step 6	Go to Step 4
4	Turn OFF the ignition. Disconnect the inoperative low beam headlamp. Connect a test lamp between the headlamp low beam supply voltage circuit of the inoperative headlamp and a good ground. Turn ON the ignition with the engine OFF. Does the test lamp illuminate?	Go to Step 5	Go to Step 21
5	Turn OFF the ignition. Connect a test lamp between the headlamp low beam supply voltage circuit of the inoperative low beam headlamp and the ground circuit of the inoperative low beam headlamp. Turn ON the ignition, with the engine OFF. Does the test lamp illuminate?	Go to Step 20	Go to Step 22
6	Do the high beam headlamps operate properly?	Go to Step 7	Go to Step 9
7	Turn OFF the ignition. Remove the headlamp low beam relay. Connect a test lamp between the switch side supply voltage circuit of the headlamp low beam relay and a good ground. Turn ON the ignition with the engine OFF. Does the test lamp illuminate?	Go to Step 8	Go to Step 23
8	Turn OFF the ignition. Connect a 40-amp fused jumper between the switch side supply voltage circuit of the headlamp low beam relay and the headlamp low beam supply voltage circuit of the headlamp low beam relay. Turn ON the ignition, with the engine OFF. Did both of the low beam headlamps illuminate?	Go to Step 17	Go to Step 24
9	Turn OFF the ignition. Install a scan tool. Turn ON the ignition, with the engine OFF. Turn ON the headlamp switch. With a scan tool, observe the Head Lamp Switch parameter in the Dash Integration Module (DIM) Inputs Data List. Does the scan tool indicate that the Head Lamp Switch parameter is ON?	Go to Step 10	Go to Step 12
10	Turn OFF the ignition. Remove the headlamp low beam relay. Connect a test lamp between the coil side supply voltage circuit of the headlamp low beam relay and a good ground. Turn ON the ignition with the engine OFF. Does the test lamp illuminate?	Go to Step 11	Go to Step 15
11	Turn OFF the ignition. Connect a test lamp between the coil side supply voltage circuit of the headlamp low beam relay and the headlamp low beam relay control circuit. Turn ON the ignition with the engine OFF. Place the headlamps dimmer switch in the low beam position. With a scan tool, command the High/Low Beam Relay ON and OFF from the DIM Special Functions, Output Control data list. Does the test lamp turn ON and OFF with each command?	Go to Step 17	Go to Step 16
12	Test for an open or a high resistance in the headlamp switch headlamp on signal circuit of the multifunction, turn signal switch. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?	Go to Step 30	Go to Step 13
13	Test for an open or high resistance in the ground circuit of the multifunction, turn signal switch. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?	Go to Step 30	Go to Step 14
14	Turn OFF the ignition. Connect a 3-amp fused jumper wire between the headlamp switch headlamp on signal circuit at the multifunction, turn signal switch and a good ground. Turn ON the ignition, with the engine OFF. Do the low beam headlamps illuminate?	Go to Step 18	Go to Step 19
15	Test for an open or high resistance in the coil side supply voltage circuit of the headlamp low beam relay. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?	Go to Step 30	Go to Step 19
16	Test for an open or high resistance in the headlamp low beam control circuit of the headlamp low beam relay. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?	Go to Step 30	Go to Step 19
17	Inspect for poor connections at the headlamp low beam relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?	Go to Step 30	Go to Step 25
18	Inspect for poor connections at the harness connector of the multifunction, turn signal switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?	Go to Step 30	Go to Step 26
19	Inspect for poor connections at the harness connector of the DIM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?	Go to Step 30	Go to Step 27
20	Inspect for poor connections at the harness connector of the HID headlamp assembly. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?	Go to Step 30	Go to Step 28
21	Repair an open or high resistance in the supply voltage circuit of the inoperative low beam headlamp. Refer to Circuit Testing and Wiring Repairs . Did you complete the repair?	Go to Step 30	-
22	Repair an open or high resistance in the ground circuit of the low beam headlamps. Refer to Wiring Repairs . Did you complete the repair?	Go to Step 30	-
23	Repair an open or high resistance in the switch side supply voltage circuit of the headlamp low beam relay switch. Refer to Wiring Repairs . Did you complete the repair?	Go to Step 30	-
24	Repair an open or high resistance in the headlamp low beam supply voltage circuit. Refer to Circuit Testing and Wiring Repairs . Did you complete the repair?	Go to Step 30	-
25	Replace the headlamp low beam relay. Refer to Relay Replacement (Attached to Wire Harness) or Relay Replacement (Within an Electrical Center) . Did you complete the replacement?	Go to Step 30	-
26	Replace the multifunction, turn signal switch. Refer to Turn Signal Multifunction Switch Replacement . Did you complete the replacement?	Go to Step 30	-
27	Replace the DIM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?	Go to Step 30	-
28	Replace the inoperative HID headlamp arc tube. Refer to High Intensity Discharge Headlamp Starter/Arc Tube Replacement . Do the headlamps operate properly?	Go to Step 30	Go to Step 29
29	Replace the inoperative headlamp leveling module.Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?	Go to Step 30	-
30	Operate the system in order to verify the repair. Did you correct the condition?	System OK	Go to Step 2