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BigBlock434, Chevy Mechanic
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2008 CHEVY: hi ,iv got a code CO561 AND A COO40 CODE

Resolved Question:

hi ,iv got a code CO561 AND A COO40 CODE IN A 2008 CHEVY 2500 WHAT CAUSES THEM TO COME ON?
Submitted: 7 years ago.
Category: Chevy
Expert:  BigBlock434 replied 7 years ago.
DTC C0561

Diagnostic Instructions

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
Review Strategy Based Diagnosis for an overview of the diagnostic approach.
Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC C0561 71: System Disabled Information Stored Invalid Serial Data Received

DTC C0561 72: System Disabled Information Stored Alive Counter Incorrect or not Updated

DTC C0561 74: System Disabled Information Stored Value of Signal Protection Calculation Incorrect

Circuit/System Description

The electronic brake control module (EBCM) receives messages from other modules over GMLAN which are needed to perform antilock brake system (ABS), vehicle stability enhancement system (VSES), or traction control system (TCS) functions.

Conditions for Running the DTC

The ignition switch is in the ON position.
Ignition voltage is greater than 9.5 volts.

Conditions for Setting the DTC

The EBCM receives an invalid message from another module over GMLAN which causes EBCM to deactivate ABS, VSES, TCS, etc.


DTC C0040 02: Right Front Wheel Speed Sensor Circuit Short to Ground

DTC C0040 05: Right Front Wheel Speed Sensor Circuit Short to Battery or Open

DTC C0040 0F: Right Front Wheel Speed Sensor Circuit Erratic

DTC C0040 18: Right Front Wheel Speed Sensor Circuit Signal Amplitude Below Minimum



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