GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2002 🢒 Eldorado 🢒 DTC 🢒 DTC B1981

Circuit Description

The BCM and IPC monitor their input voltages to determine if it is above 10.0 V.

Conditions for Setting the DTC

The IPC measures the following conditions:

    • The engine speed greater than 1500 RPM
    • The battery positive voltage at the IPC or BCM 10 V for 2 seconds.

Action Taken When the DTC Sets
    • The IPC displays the BATTERY VOLTAGE LOW message on the driver message center.
    • If the voltage falls below approximately 9.0 V, the IPC turns off all of the unneeded dimming VF display circuits.

Step

Action

Value(s)

Yes

No

Schematic Reference: Control Module References

1

Did you perform the Engine Electrical Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Engine Electrical

2
  1. Install a scan tool.
  2. Start the engine.
  3. Raise the engine RPM above 1,500.
  4. With a scan tool, observe the Battery Voltage in the affected module data list and record.

Does the scan tool indicate the battery voltage is above specified value?

10.0 V

Go to Step 7

Go to Step 3

3
  1. Turn OFF the ignition.
  2. Disconnect the affected module. Refer to Control Module References in Body Control System.
  3. Measure the voltage from the battery positive voltage circuit of the affected module to the ground circuit of the affected module.

Does the voltage measure near the value recorded in step 2?

--

Go to Charging System Test

Go to Step 4

4

Measure the voltage from the battery positive voltage circuit of the affected module to a good ground.

Does the voltage measure near the value recorded in step 2?

--

Go to Step 6

Go to Step 5

5

Test the battery positive voltage circuit of the affected module for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 9

Go to Step 7

6

Test the ground circuit of the affected module for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 9

Go to Step 8

7

Inspect for poor connections at the harness connector of the affected module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 9

Go to Step 8

8

Important: Perform the setup procedure for the affected module if applicable.

Replace the affected module. Refer to Control Module References in Body Control System.

Did you complete the replacement?

--

Go to Step 9

--

9
  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 2

System OK