GM Service Manual Online
For 1990-2009 cars only

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 B1433 00: Ignition Switched Power Relay 2 Circuit

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Ignition 3 Voltage

B1433 00

1

2

--

  1. No power at multiple fuses or components in the RUN position.
  2. Some components may remain powered and cause a battery drain condition.

Circuit/System Description

The body control module (BCM) supplies voltage to the HVAC module and the windshield washer solvent heater (RPO XA7), and the control circuit of the RUN PCB relay (TP2) through the ignition 3 voltage circuit. voltage is applied when any of the following conditions are true:

    • Ignition Switch is in ACC or RUN.
    • The vehicle was remote started.
    • The vehicle is in retained accessory power (RAP) mode.

Conditions for Running the DTC

    • The system voltage is between 9-16 volts.
    • The DTC can only set when the output is actively being requested by the module.

Conditions for Setting the DTC

The DTC will set only when the module requests the output and there is a short to ground in the run relay coil control circuit.

Action Taken When the DTC Sets

The module output driver will be shut down and not supply voltage to the circuit.

Conditions for Clearing the DTC

    • The current DTC will clear when the module request for the output is removed or the malfunction is no longer present.
    • A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.

Diagnostic Aids

    • A short to voltage may cause some accessories to operate with the ignition key out and cause a low battery after extended non vehicle use.
    • PCB relays are soldered on the fuse block and cannot be replaced separate from the fuse block. If PCB relay replacement is necessary the fuse block will need to be replaced.

Reference Information

Schematic Reference

    •  Body Control System Schematics
    •  Power Distribution Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Retained Accessory Power Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Testing

  1. Ignition ON, verify DTC B1433 is set as current.
  2. If DTC B1433 is not set as current, operate the vehicle within the Conditions for Setting the DTC.

    Important: When cycling the ignition, keep ignition OFF for 5 seconds before checking for current DTC.

  3. Ignition OFF, disconnect each of the following components one at a time. After each component is disconnected, cycle the ignition and verify DTC B1475 remains set as current. The components may be disconnected in any order.
  4. • HVAC module X2
    • Windshield washer solvent heater X2 (with RPO XA7)
    If DTC B1433 does not remain set as current, test or replace the last component that was disconnected.
  5. Ignition OFF, disconnect the X5 harness connector at the BCM.
  6. Test for greater than 70 ohms of resistance between the BCM ignition 3 voltage circuit terminal 13 and ground.
  7. If less than specified, test the control circuit for a short to ground. If the circuit tests normal, replace the underhood fuse block.
  8. If the circuit tests normal, test or replace the BCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

    •  Windshield Washer Solvent Heater Replacement
    •  Underhood Electrical Center or Junction Block Replacement
    •  Control Module References for module replacement, setup, and programming