Diagnostic Aids

WARNING: This page is about a different car, the 2009 GMC Sierra and 2009 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.

When the percent duty cycle of the contactor system request circuit is 65-75 percent, the BECM will request the 300 volt battery contactors to OPEN.
When the percent duty cycle of the contactor system request circuit is 25-35 percent, the BECM will request the 300 volt battery contactors to CLOSE.
The frequency of the PWM signal must be between 247 Hz to 253 Hz to be valid.