Possible Open Fuse in Fuse Block–Battery

Some 2019 Silverado and Sierra models equipped with the 2.7L 4-cylinder engine (RPO L3B) may have an engine will not crank condition. If this condition is found and the starter motor does not rotate during an engine crank request, test for an open F3BA 400 amp fuse in the X50D Fuse Block–Battery. (Fig. 23)


Fig. 23


If the F3BA 400 amp fuse is open, test for infinite resistance between the test points: B+ circuit terminal A X2 at the M64 Starter Motor and ground. If there is less than infinite resistance, repair the short to ground condition on the circuit.

If there is infinite resistance, replace the X50D Fuse Block–Battery and retest for proper engine cranking. Do not replace the starter motor.

If the F3BA 400 amp fuse is not open, follow the appropriate starter diagnostic information in the Service Information.


– Thanks to Raymond Haglund



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