Test Notes
Normal OperationThe diagnostic monitor measures the voltage at Pin 11 Circuit 614A (GY/O) of the diagnostic monitor connector. The voltage at Pin 11 varies with the charging system voltage.
PIN 11 VOLTAGE CHART
Charging System Voltage Voltage at Pin 11
9.0 1.9
9.5 2.0
10.0 2.1
10.5 2.2
11.0 2.3
11.5 2.4
12.0 2.5
12.5 2.6
13.0 2.7
13.5 2.7
14.0 2.9
14.5 3.0
15.0 3.1
15.5 3.2
16.0 3.3
Note that Circuit 614A (GY/O) is connected to Circuits 614 (GY/O) and 614B (GY/O). Also note that Circuit 614A (GY/O) is connected to 615 (GY/W) through the driver side air bag and Circuit 616 (PK/BK) through the passenger side air bag. Additionally, note that Circuit 615 (GY/W) and 616 (PK/BK) are connected to the RH, LH and Center Radiator Crash Sensor Feed Circuits 617 (PK/O), 619 (PK/W), 621 (W/Y) through diodes inside the diagnostic monitor. If the diagnostic monitor measures a voltage of 2.0 volts or less at pin lithe monitor will flash a code 13 to indicate a possible short to ground on this circuit. When flashing code 13, the diagnostic monitor blows its internal thermal fuse. This disables the air bag deployment circuit. If the voltage at pin 11 returns to normal (because the short to ground no longer exists), a diagnostic trouble code 51 will be present on the air bag indicator, due to the open thermal fuse.
Possible Causes
Low voltage at diagnostic monitor pin 11 can be caused by:
1. A short to ground within the wiring harness on wires Circuits 614 (GY/O), 614A (GY/O), 614B (GY/O), 615 (GY/W), 616 (PK/BK), 617 (PK/O), 619 (PK/W), 621 (W/Y) or 623 (P/W) causing the diagnostic monitor voltage to drop.
2. An internal short to ground within the clockspring assembly causing the driver and passenger side air bag circuit(s) to be shorted to ground.
3. An internal short to ground within the safing sensors causing Circuits 614 (GY/O), 614A (GY/O) or 623 (P/W) to be shorted to ground.
4. An internal short to ground within one or more of the crash sensors causing Circuits 617 (PK/O), 619 (PK/W), and 621 (W/Y) to be shorted to ground.
NOTE: Circuits 617 (PK/O), 619 (PK/W) and 621 (W/Y) are all connected together inside the diagnostic monitor. Therefore, a short to ground on any of these circuits will short all of the circuits to ground.
5. An internal short to case ground within the driver side air bag or passenger side air bag.