GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2004 🢒 Colorado Pickup - 4WD 🢒 DTC 🢒 DTC B1000

Circuit Description

Each control module runs a program to detect internal memory faults. No external circuits are involved. If a control module detects any type of internal memory fault, that control module may set DTC B1000.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B1000 Electronic Control Unit (ECU) Performance

Conditions for Running the DTC
    • The control module has power and ground.
    • The ignition is ON.

Conditions for Setting the DTC

DTC B1000 will set if either of the following conditions occur:

    • The control module detects an internal write malfunction.
    • The control module detects an internal checksum malfunction.

Action Taken When the DTC Sets

Any of the following actions may occur:

    • The control module refuses all additional inputs.
    • The control module requests the malfunction indicator lamp (MIL).
    • The check gages chime sounds.

Conditions for Clearing the DTC
    • A current DTC clears when the ignition is cycled, and the malfunction is no longer present.
    • A history DTC clears when the ignition is cycled 100 times without a repeat of the malfunction.

Diagnostic Aids
    • DTC B1000 may be stored as a history DTC without affecting the operation of the module. If stored only as a history DTC and not retrieved as a current DTC, do not replace the module.
    • If DTC B1000 is retrieved as both a current and history DTC, replace the module that set the DTC.

Step

Action

Yes

No

1

Did you perform the Diagnostic System Check for the system exhibiting the symptom?

Go to Step 2

Go to Control Module References for the applicable Diagnostic System Check

2
  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Retrieve DTCs with the scan tool.

Is DTC B1000 retrieved as a current DTC?

Go to Step 3

Go to Diagnostic Aids

3

Important: Perform the programming or setup procedure for the module, if required.

Replace the control module that set DTC B1000 as current. Refer to Control Module References for the replacement procedure.

Did you complete the replacement?

Go to Step 4

--

4
  1. Clear the DTCs with the scan tool.
  2. Operate the vehicle within the Conditions for Running the DTC.

Does DTC B1000 reset?

Go to Step 2

System OK