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Brake Light Switch: Testing and Inspection






STOP LAMP SWITCH





NOTE: Before proceeding with this diagnostic test, verify the adjustment lever on the back of the switch is in the adjusted position. If the lever is in the non-adjusted (diagonal) position it may have never been adjusted.

If the electrical circuit has been tested and the stop lamp switch is suspected of being damaged or inoperative, it can be tested using the following method.

1. Remove the switch from the vehicle.

2. With the switch in the released position (plunger extended), use an ohmmeter to test each of the three internal switches as shown. You should achieve the results as listed in the figure.





3. Gently push the plunger on the stop lamp switch in until it stops.

4. With the switch in this depressed position (plunger pushed in), use an ohmmeter to test each of the three internal switches as shown. You should achieve the results as listed in the figure.

If you do not achieve the results as listed in both figures, the switch must be replaced.

If the switch is found to be operating properly, it may be misadjusted. Do not reinstall the switch, replace it.

CAUTION: The switch can only be adjusted once. That is during initial installation of the switch. If the switch is not adjusted properly or has been removed for any reason, a new switch must be installed and adjusted.