DTC P1381 Misfire Detected - No Communication with Brake Control Module. Chevrolet Blazer

For 1990-2009 cars only

Makes 🢒 Chevrolet 🢒 2000 🢒 Blazer - 4WD 🢒 Engine 🢒 Engine Controls - 4.3L 🢒 DTC P1381 Misfire Detected - No Communication with Brake Control Module

Handling ESD Sensitive Parts Notice
Handling ESD Sensitive Parts Notice
Handling ESD Sensitive Parts Notice
Handling ESD Sensitive Parts Notice
Handling ESD Sensitive Parts Notice
Handling ESD Sensitive Parts Notice
Handling ESD Sensitive Parts Notice
Handling ESD Sensitive Parts Notice
Handling ESD Sensitive Parts Notice
Engine Controls Components
Data Link Connector (DLC)
OBD II Symbol Description Notice

Circuit Description

This diagnostic will detect a loss of serial communication from the electronic brake control module (EBCM) to the control module. This serial communication is essential in order to distinguish misfire from a rough road condition.

Conditions for Running the DTC

•	Misfire DTC is active

•	MIL is requested

•	No rough road ABS data information is available

Conditions for Setting the DTC

A serial data malfunction is preventing the VCM from receiving rough road detection data.

Action Taken When the DTC Sets

•	The control module stores the DTC in history after the first failure but will not illuminate the malfunction indicator lamp (MIL).

•	The control module 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/DTC

•	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 temperature exceeds 70°C (160°F) during the same ignition cycle.

•	Use the scan tool Clear Information function.

An intermittent may be caused by any of the following conditions:

•	A poor connection

•	Rubbed through wire insulation

•	A broken wire inside the insulation

Thoroughly inspect any circuitry that is suspected of causing the intermittent complaint. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

If a repair is necessary, refer to Wiring Repairs or Connector Repairs in Wiring Systems.

Test Description

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

This step isolates an open serial data circuit from the EBCM system.

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	Check for any U-Codes. Did you find any U-Codes?	--	Go to applicable DTC	Go to Step 3
3	Disconnect the VCM and EBCM. Check the serial data circuit between the VCM and the EBCM for an open or poor connection. Did you find a problem?	--	Go to Step 4	Go to Diagnostic System Check in Antilock Brake Systems
4	Repair the circuit as necessary. Refer to Wiring Repairs or Connector Repairs in Wiring Systems. Is the action complete?	--	Go to Step 5	--
5	Use the scan tool in order to Clear the DTCs. Start the engine. Allow the engine to idle until the engine reaches normal operating temperature. Select DTC and the Specific DTC function. Enter the DTC number which was set. Operate the vehicle within the Conditions for Setting this DTC, until the scan tool indicates that the diagnostic Ran. Does the scan tool indicate that the diagnostic Passed?	--	Go to Step 6	Go to Step 2
6	Does the scan tool display any additional undiagnosed DTCs?	--	Go to applicable DTC	System OK