For 1990-2009 cars

Step | Action | Values | Yes | No
--- | --- | --- | --- | ---
Caution: Do not insert test equipment probes (DMM etc.) into any connector or fuse block terminal. The diameter of the test probes will deform most terminals. A deformed terminal will cause a poor connection, which will result in a system failure. Always use the J-35616 GM-Approved Terminal Test Kit in order to front probe terminals. Do not use paper clips or other substitutes to probe terminals. When using the J-35616 GM-Approved Terminal Test Kit, ensure the terminal test adapter choice is the correct size for the connector terminal. Do not visually choose the terminal test adapter because some connector terminal cavities may appear larger than the actual terminal in the cavity. Using a larger terminal test adapter will damage the terminal. Refer to the J-35616 GM-Approved Terminal Test Kit label on the inside of the J-35616 GM-Approved Terminal Test Kit for the correct adapter along with the connector end view for terminal size.
1 | Inspect fuse EF19. Is fuse EF19 open? | -- | Go to Step 2 | Go to Step 3
2 |

1. Inspect for a short circuit and repair it, if necessary.
2. Replace the fuse.

Is the repair complete?

--

System OK

--

3 |

1. Press the brake pedal down.
2. Inspect the positive terminals of the bulb sockets with a test lamp.

Does the test lamp illuminate?

--

Go to Step 4

Go to Step 6

4 | Connect an ohmmeter between ground and the stop lamp ground terminal. Is the resistance equal to the specified value? | 0 Ω | Go to Step 6 | Go to Step 5
5 | Repair the ground circuit. Is the repair complete? | -- | System OK | --
6 |

1. Disconnect the wiring connector from the stop lamp switch.
2. Press the brake pedal down.
3. Use an ohmmeter to measure continuity between terminals 3 and 4.

Is the resistance equal to the specified value?

0 Ω

Go to Step 8

Go to Step 7

7 | Replace the stop lamp switch. Is the repair complete? | -- | System OK | --
8 |

1. Disconnect the stop lamp switch electrical connector.
2. Measure the voltage at terminal 3.

Does the voltage measure within the specified range?

11-14 V

Go to Step 10

Go to Step 9

9 | Repair the open circuit between the fuse EF19 and the stop lamp switch. Is the repair complete? | -- | System OK | --
10 | Repair the open circuit between the stop lamp switch and the stop lamps. Is the repair complete? | -- | System OK | --