DTC C0201. GMC Truck Envoy

For 1990-2009 cars only

Makes 🢒 GMC_Truck 🢒 2007 🢒 Envoy - 2WD 🢒 Driver Information and Entertainment 🢒 Cellular, Entertainment, and Navigation 🢒 DTC C0201

Circuit Description

The system relay, located within the electronic brake control module (EBCM), supplies battery voltage to all of the solenoid valves. When the relay contacts close, the EBCM monitors the voltage supplied to the solenoid valves and compares this voltage to monitored ignition voltage.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC C0201 Antilock Brake System (ABS) Enable Relay Contact Circuit

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

Either of the following conditions may cause the DTC to set:

•	The EBCM detects that the voltage supplied to the valve solenoids is less than 65 percent of the monitored ignition voltage for 50 milliseconds.

•	The EBCM detects that the relay contacts do not open when the relay is not energized.

Action Taken When the DTC Sets

If equipped, the following actions occur:

•	The EBCM disables the ABS/traction control system (TCS)/vehicle stability enhancement system (VSES)/dynamic rear proportion (DRP).

•	The ABS indicator turns ON.

•	The stability indicator turns ON.

•	The brake warning indicator turns ON.

Conditions for Clearing the DTC

The Conditions for Setting the DTC are no longer present and you use the scan tool Clear DTCs function.

Diagnostic Aids

Refer back to the diagnostic table, steps 3-7, if this DTC continues to set intermittently.

Test Description

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

A shorted ABS pump motor may damage the contacts within the system relay. It is imperative that the steps in the table be followed to prevent damage to a replacement EBCM.

Step	Action	Values	Yes	No
Schematic Reference: Antilock Brake System Schematics Connector End-View Reference: Antilock Brake System Connector End Views
1	Did you perform the Diagnostic System Check - Vehicle?	--	Go to Step 2	Go to Diagnostic System Check - Vehicle
2	Use the scan tool to clear the DTCs. Turn OFF the ignition for 5 seconds. Turn ON the ignition. Does the DTC reset?	--	Go to Step 3	Go to Diagnostic Aids
3	Separate the electronic brake control module (EBCM) from the brake pressure modulator valve (BPMV). Refer to Electronic Brake Control Module Replacement . Use a DMM in order to measure the resistance across the ABS pump motor. Does the resistance measure within the specified range?	0.3-1 ohms	Go to Step 4	Go to Step 6
4	Use a DMM in order to measure the resistance between the high side of the pump motor and a good ground. Does the resistance measure less than the specified value?	OL	Go to Step 6	Go to Step 5
5	Important: Following the EBCM replacement, perform the set-up procedure for the EBCM. Use the scan tool to perform the Tire Size Calibration procedure. Replace the EBCM. Refer to Control Module References . Did you complete the replacement?	--	Go to Step 7	--
6	Important: Following the EBCM replacement, perform the set-up procedure for the EBCM. Use the scan tool to perform the Tire Size Calibration procedure. Replace the EBCM and the BPMV. Refer to Control Module References . Did you complete the replacements?	--	Go to Step 7	--
7	Use the scan tool to clear the DTCs. Turn OFF the ignition for 5 seconds. Turn ON the ignition. Does the DTC reset?	--	Go to Step 3	System OK