DTC 22: Center Cowl Safing Sensor Output Circuit Shorted to B+
Electrical Schematic:
Pin 11 And 12 Voltage Chart:
Normal Operation
The air bag diagnostic monitor measures the voltage at pins 11 (circuit 944A "GN/W") and 12 (circuit 944B "GN/W"). The voltage at these pins is controlled by two resistors inside the air bag diagnostic monitor (along with the resistors inside the air bag sensors - see normal operation for code 24 for more information). This voltage varies with the charging system voltage as shown in the chart provided.
If the voltage at both of these pins exceeds 5 volts, the air bag diagnostic monitor will flash a code 22.
Possible Causes
High voltage at pins 11 and 12 can be caused by the following:
1. A short to power in the wiring harness between circuits 944 "GN/W", 944A "GN/W", 944B "GN/W", 944D "GN/W" or 938 "R" and another wire can cause high voltage on these circuits.
NOTE: The wiring harness leading to the center cowl safing rear air bag sensor and bracket carries higher voltage circuits that may short to circuits 944 and 938.
2. A short in the air bag sliding contact between circuit 938 and the horn or speed control wiring.
3. A short across the normally open contacts of the center cowl safing rear air bag sensor.
NOTE: The voltage at circuits 951 and 943 inside the center cowl safing rear air bag sensor is usually battery voltage or higher. There should be an open circuit across the contacts of the center cowl safing rear air bag sensor if the center cowl safing rear air bag sensor is operating normally. If the sensor contacts are closed, the voltage on circuits 944 and 938 would be high (at least battery voltage).
4. Vehicle charging system voltage too high. If the generator output voltage is too high (greater than 17 volts), a code 22 may occur.
Pinpoint Test Steps: