Result:

p1842

GM
Type:
    Powertrain - Manufacturer Controlled DTC - Manufacturer Controlled
Description:
    1-2 Shift Solenoid Circuit Low Input (4T80-E Transmission)
Cause:
    Engine runtime over 5 seconds, system voltage from 8-18v, Fuel Cutoff inactive, then the PCM detected an open circuit or a short to ground on the 1-2 Shift Solenoid feedback circuit for 4.3 seconds.

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