Location of ground for ebcm on 2001 denali

Question edited for clarity. The codes are C-Zero, not C-Oh.

C0281 CHEVROLET - Engine-Codes.com

https://www.engine-codes.com > c0281_chevrolet
'What is C0281 CHEVROLET code meaning? ... The stop lamp switch signal informs the Electronic Brake Control Module (EBCM) when the brake pedal is pressed. The ..

C0222 CHEVROLET Code - Missing Right Front Speed Signal

https://www.engine-codes.com > c0222_chevrolet
'C0222 CHEVROLET code possible causes · Faulty Right Front Speed Sensor · Right Front Speed Sensor harness is open or shorted · Right Front Speed Sensor circuit ...

C0265 Engine Code: EBCM Relay Circuit - Diagnosis & Repair

https://chevytrucks.org > c0265-engine-code-repair
Aug 19, 2020 - On Chevy and GMC vehicles, this engine code is caused by a bad connection at the EBCM ground, which is located inside of the unit itself. If you ...

ABS code not check engine light code .
DTC C0201 00: Antilock Brake System (ABS) Enable Relay Contact Circuit
The solenoid relay, located within the electronic brake control module (EBCM), supplies battery voltage to all of the valve solenoids.
Circuit/System Verification
With scan tool installed, clear the DTCs then drive the vehicle in a straight line at a speed greater than 20 km/h (13 mph). If the DTC did not set as a current DTC see diagnostic aids.
Circuit/System Testing
Test for an open or a short to ground in the battery positive voltage circuit to the EBCM. Verify no open or a short to ground is found.
Test the EBCM ground circuit, an open or high resistance.
? If an open or a short to ground is found, repair the circuit.
Replace the EBCM assembly.

DTC C0201 (Equal to or over 8600 GVW)
The system relay, located within the electronic brake control module (EBCM), supplies battery voltage to all of the valve solenoids and to the Antilock Brake System (ABS) pump motor. When the relay contacts close, the EBCM monitors the voltage supplied to the valve solenoids and compares this voltage to monitored ignition voltage.
Action Taken When the DTC Sets
• The EBCM disables the ABS/DRP.
• The ABS indicator turns ON.
• The brake warning indicator turns ON

The EBCM is located on the drivers side frame rail under the truck. There are 5 brake lines that run into the unit.

Visit the on-line store, know as reliable-store, they have the repair manuals. I'm sure you will get the solution of your problem.
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Diagnostic Test Code (DTC) C0265 is a POWER circuit code for the EBCM/Pump Motor Relay, not a ground code. This DTC sets when the voltage (B+) is too low at the EBCM when the solenoids and pump motor are commanded OFF. The voltage is supposed to be pulled low when the circuit is commanded ON. A ground problem with the EBCM is most likely to cause a failure of the EBCM to communicate with a scan tool. However, it doesn't hurt anything to check the ground. The main ground for the EBCM (G106) is located on the left rear of the engine near the knock sensor.

looks like you need an ebcm. You can check the ground under the drivers side door attached to the frame, make sure it is clean and tight.



DTC C0241-C0254 or C041-C054
Circuit DescriptionThe ABS relay supplies battery voltage to 6 valve solenoids. The electronic brake control module (EBCM) microprocessor applies the grounds needed to activate each solenoid. The low side of each solenoid coil has a feedback circuit to the EBCM microprocessor. When a solenoid is commanded OFF, the feedback voltage is high. When a solenoid is commanded ON, the feedback voltage is low.
Conditions for Running the DTC • The ignition is ON. • The vehicle speed is greater than 6 km/h (4 mph). Conditions for Setting the DTCThe EBCM detects an internal malfunction.
Action Taken When the DTC Sets C0241, C0242, C0245, C0246, C0251, C0252, C0253, C0254If equipped, the following actions occur:
• The EBCM disables the DRP/ABS. • The ABS indicator turns ON. • The red brake warning indicator turns ON. C0243, C0244, C0247, C0248If equipped, the following actions occur:
• The EBCM disables the ABS. • The ABS indicator turns ON. Conditions for Clearing the DTCThe conditions for setting the DTC are no longer present and you use the scan tool Clear DTCs function.
Diagnostic AidsAn intermittent open/shorted solenoid DTC can be set by several different internal EBCM problems. Replace the EBCM if an open/shorted solenoid DTC continues to set intermittently.
Step
Action
Yes
No
1
Did you perform the ABS Diagnostic System Check?
Go to Step 2
Go to Diagnostic System Check - ABS
2

1. Use a scan tool in order to clear the DTCs.
2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC set?
Go to Step 3
Go to Diagnostic Aids
3
Important: Following EBCM replacement, use the scan tool to perform the Tire Size Calibration procedure and the Trim Level Calibration procedure, if applicable.
Replace the EBCM. Refer to Electronic Brake Control Module Replacement .
Did you complete the replacement?
Go to Step 4
--
4

1. Use the scan tool in order to clear the DTCs.
2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?
Go to Step 3
System OK

Hello,
There is a ground wire connected to the engine block. Look for it on the back passenger side of the engine towards the top. Remove it and clean the connection and the wire connector and replace. Sometimes they get real bad and throw the ABS light on. Sometimes a brake light out can throw the ABS light on.

• You said you rebuilt the ABS module, do you have a short in it you are missing? The bulletin for this originally suggested to replace the module and was corrected because the ground itself was the major offender.
• Try to reground the EBCM. The code 0265 says "loss of communication with the brake module" The EBCM Ground is located on the frame beneath the driver's side door. If multiple grounds are found in this location, the EBCM ground can be identified as the heavy (12-gauge) wire. Clean the area, front and back, using a Whiz Wheel.

• Install the ground, then the washer and then the bolt to the frame. Important: It is important to use the bolts, washers and nuts specified in this bulletin. These parts have been identified due to their conductive finish.
• Install a washer and nut to the back side of the frame.
• Tighten the nut to 9 N·m (79 lb in).

• Cover the front and back side of the repair area using Rubberized Undercoating. An additional check can be made to ensure a good connection for the Battery Cable to Frame ground.

Regards, Tony

it is located along the frame rail under the truck on the driver side, should be near the back of the cab. look for the pump with the metal hard lines leading from it.

Now check the ground to those lights to make sure it's connections on both ends are tight and not corroded. Once you are sure that the ground is good, if you still don't have lights it must be the switch, located at the base of the brake pedal. J.

Start at the exhaust manifold flange on the drivers side. The first sensor you come to before the cat. converter is the sensor you are looking for.