Saturn: Engine Does Not Crank, Dimmer Switch To Blame – UnderhoodService

Saturn: Engine Does Not Crank, Dimmer Switch To Blame

Model: 2002 Saturn LW200, 2.2L

Saturn dimmer switchComplaint

The customer states the engine does not crank.


Confirmed the customer’s complaint and found the engine did not crank. Performed a visual inspection of the battery cables and found no obvious faults. Used a multimeter to measure the voltage across the battery terminals and found the measured voltage was below the specified range. Charged the battery and continued the diagnosis.

Used a battery conductance tester to test the battery and found the battery was able to conduct the specified amount of current, which verified it operated properly. Connected an inductive ammeter around the negative battery cable to measure the parasitic draw on the battery and found the measured parasitic draw was above specifications.

Noticed the interior lights stayed on with the doors closed. Removed the interior lights fuse and found the excessive parasitic draw was no longer present and the interior lights turned off. Disconnected the interior lights override switch and found the interior lights turned off. Used the multimeter to check the continuity of the interior lights override switch and found the switch had continuity in the off position.

The result of these tests verified the interior lights override switch was faulty. The interior lights override switch is integrated into the instrument panel light dimmer switch and is replaced as an entire unit.


Replaced the instrument panel light dimmer switch and verified the vehicle operated properly. The customer’s concern did not return.

Courtesy of Mitchell 1 SureTrack Real Fixes

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