Circuit Description

1999 Chevrolet Chevy Express G1500, Van Cargo, 5.7 RSECTION Circuit Description

Ignition voltage is supplied directly to 2nd gear block out or skip shift solenoid coil. PCM controls solenoid by grounding control circuit through an internal switch called a driver. Primary function of driver is to supply ground for component being controlled. Each driver has a fault line which is monitored by PCM.

When PCM is commanding a component ON, voltage of control circuit should be low (near zero volts). When PCM is commanding control circuit to a component OFF, voltage potential of circuit should be high (near battery voltage). If fault detection circuit senses a voltage other than what is expected, fault line status will change, causing DTC to set.

Conditions for setting DTC are: engine speed is greater than 600 RPM, ignition voltage is greater than 6 volts but less than 16 volts, PCM detects commanded state of driver and actual state do not match and conditions met for 10 seconds.

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

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