DTC P0601. Chevrolet Astro

For 1990-2009 cars only

Makes 🢒 Chevrolet 🢒 2000 🢒 Astro - 2WD 🢒 Engine 🢒 Engine Controls - 4.3L 🢒 DTC P0601

Circuit Description

The control module programmable read only memory (PROM) contains data which is essential to the operation of the engine and the transmission. When the ignition is turned ON, the values in all of the PROM memory locations are added together and compared to a calibrated checksum number. This test determines if any address locations have become corrupt.

Since this diagnostic pertains to an internal vehicle control module (VCM) diagnostic check, no wiring schematic is required.

Conditions for Running the DTC

The ignition switch is in the Crank position or in the Run position.

Conditions for Setting the DTC

The VCM is unable to correctly read data from the flash memory.

Action Taken When the DTC Sets

•	The control module illuminates the malfunction indicator lamp (MIL) the first time the diagnostic runs and fails.

•	The control module will set the DTC and records the operating conditions at the time the diagnostic fails. The control module stores the failure information in the scan tools Freeze Frame/Failure Records.

Conditions for Clearing the MIL or DTC

•	The control module turns OFF the MIL after 3 consecutive drive trips when the test has run and passed.

•

A history DTC will clear if no fault conditions have been detected for 40 warm-up cycles. A warm-up cycle occurs when the coolant temperature has risen 22°C (40°F) from the startup coolant temperature and the engine coolant reaches a temperature that is more than 70°C (158°F) during the same ignition cycle.

•	Use a scan tool in order to clear the DTCs.

Diagnostic Aids

Replace the VCM even if this DTC exists only in history. Refer to VCM Replacement/Programming .

Test Description

The number below refers to the step number on the diagnostic table.

Replace the VCM even if this DTC exists only in history.

Step	Action	Values	Yes	No
1	Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?	--	Go to Step 2	Go to Powertrain On Board Diagnostic (OBD) System Check
2	Important: The replacement VCM must be programmed. Replace the VCM. Refer to VCM Replacement/Programming . Is the action complete?	--	Go to Step 3	--
3	Using the scan tool, clear the DTCs. Start the engine. Allow the engine to idle until the engine reaches normal operating temperature. Select the DTC and the Specific DTC function. Enter the DTC number which was set. Operate the vehicle within the Conditions for Setting the DTC until the scan tool indicates the diagnostic Ran. Does the scan tool indicate the diagnostic Passed?	--	Go to Step 4	Go to Step 2
4	Does the scan tool display any additional undiagnosed DTCs?	--	Go to the applicable DTC table	System OK