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1991 Pontiac Grand Prix, IC Circuit Waveform
Posted to the Waveform Library on 8/31/2001

This is what EST and Bypass voltage should look like at start up. This is with a new module installed to fix a hard code 42. During cranking the module is holding EST low which is why at the beginning of the pattern it's only a 500mv square wave. When the RPM ...

 

car Vehicle Data

1991 Pontiac Grand Prix SE 3.1L

Engine3.1 L / 6 cyl / GAS
Trans4-speed AutomaticTransaxle
DeliveryFuel Injection
SubsystemECM/Inputs/Outputs
Component
ConditionKnown Good

car Vehicle Data

1991 Pontiac Grand Prix SE 3.1L

Engine3.1 L / 6 cyl / GAS
Trans4-speed AutomaticTransaxle
DeliveryFuel Injection
SubsystemECM/Inputs/Outputs
Component
ConditionKnown Good