Test Notes and Schematics

Electrical Schematic-Diagnostic Trouble Code 33


Normal Operation
The diagnostic monitor measures the resistance across Pin 8 (Circuit 614) GY/O) and Pin 9 (Circuit 616) PK/BK) every time the ignition switch is turned to the ON position. Normal resistance across these circuits is between 0.9 ohms and 1.1 ohms. This resistance comes from the passenger side air bag itself. If the vehicle is NOT equipped with a passenger side air bag, Pin 7 of the diagnostic monitor should be connected to ground. Connecting Pin 7 to ground programs the diagnostic monitor to ignore high resistance on the passenger side air bag circuits. If the resistance across these two circuits exceeds 4.0 ohms and Pin 7 is not grounded, the diagnostic monitor will flash code 33.

NOTE: The connector for the air bag has a metal spring clip that acts as a shorting bar. This shorting bar is built into the plastic hardshell connector on the back of the passenger side air bag. The shorting bar is designed to short the air bag terminals together when the connector is not mated. DO NOT attempt to remove the air bag shorting bar and measure the resistance of the air bag.

Possible Causes
A high resistance or open in the passenger side air bag circuit can be caused by:

Vehicles not equipped with a passenger side air bag:
1. Pin 7 not connected to ground. The wire in pin location 7 in the black diagnostic monitor harness connector should be connected onto a bracket near the passenger side air bag mounting bracket.

Vehicles equipped with a passenger side air bag:
1. An open circuit or high resistance in the wiring harness in Circuit 614 (GY/O) or 616 (PK/BK).
2. An open circuit or high resistance in the passenger side air bag. DO NOT attempt a direct resistance measurement of the air bag. Follow the diagnostic procedures to determine if the air bag resistance is higher than normal.