For 1990-2009 cars

Step | Action | Yes | No
--- | --- | --- | ---
1 | Did you perform the Lighting System Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Lighting Systems
2 | Press the brake pedal. Do all of the stop lamps illuminate? | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 3
3 | Verify if only one of the stop lamps is inoperative or all stop lamps are inoperative. Is only one stop lamp inoperative? | Go to Step 12 | Go to Step 4
4 | Inspect the STOP LAMP fuse. Is the fuse open? | Go to Step 5 | Go to Step 6
5 | Repair a short to ground in one of the following circuits:

• | CKT 140

• | CKT 17

Is the repair complete?

Go to Step 15

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6 | Use a test lamp in order to backprobe the stop lamp switch harness connector C1 between terminal A and ground. Did the test lamp light? | Go to Step 7 | Go to Step 10
7 |

1. Use a test lamp in order to backprobe the stop lamp switch harness connector C1 terminal B and ground.
2. Depress and hold the brake pedal while observing the test lamp.

Did the test lamp light?

Go to Step 8

Go to Step 9

8 |

1. Use a test lamp in order to backprobe between the LH tailamp connector terminal A and ground.
2. Depress and hold the brake pedal while observing the test lamp.

Does the test lamp light?

Go to Step 14

Go to Step 11

9 | Adjust or replace the stop lamp switch. Refer to Stop Lamp Switch Replacement in Hydraulic Brakes. Is the repair complete? | Go to Step 15 | --
10 | Repair the following conditions in CKT 140:

• | A faulty connection

• | An open circuit

Is the repair complete?

Go to Step 15

--

11 | Repair the following conditions in CKT 17 between the stoplamp switch and S415:

• | A faulty connection

• | An open circuit

Is the repair complete?

Go to Step 15

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12 | Test for an open or a high resistance in the inoperative stop lamp power supply or ground supply circuit. Did you find and correct the condition? | Go to Step 15 | Go to Step 13
13 | Replace the inoperative stop lamp. Refr to Tail Lamp Replacement . Did you complete the repair? | Go to Step 15 | --
14 | Repair an open or poor connection at G401 Did you complete the repair? | Go to Step 15 | --
15 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 2