Normal Operation

The Restraints Control Module (RCM) continuously monitors the passenger air bag module stage 1 and circuits for the following faults:

• Resistance out of range
• Unexpected voltage
• Short to ground
• Faulted passenger air bag module

If a fault is detected, the RCM  will store DTC B0010:11, B0010:12, B0010:13 or B0010:1A in memory and send a message to the Instrument Cluster (IC) module to illuminate the air bag warning indicator.

The RCM  analyzes the deployment loop resistance and uses this measurement in combination with an age correction factor to determine if a fault exists. The value displayed in the PID is the deployment loop resistance as measured by the RCM  . If the value displayed is lower or higher than the desired range (refer to diagram below), the RCM  can set a DTC. As the deployment loop resistance drifts farther outside the desired range, the chance for a DTC increases. The RCM  fault trigger threshold may vary as the vehicle ages. Small variations in resistance can occur due to the effect of road vibrations on terminal fit and/or temperature changes. These variables can result in an intermittent fault. For this reason, the test will require the PID value to be within the desired range before the fault is considered repaired, regardless if the module is reporting an on-demand DTC at time of diagnosis. Following this direction will help make sure that minor changes in resistance do not create a repeat concern. This test will use a process of elimination to diagnose each part of the deployment loop circuit including:

• Wiring
• Connections
• Passenger air bag module
• RCM 
  Fig 1: RCM Analyzes Resistance Diagram

  Courtesy of FORD MOTOR CO.
  DTC DESCRIPTION CHART
  
  

  DTC Description	Fault Trigger Conditions
  B0010:11 - Passenger Frontal Stage 1 Deployment Control: Circuit Short to Ground	When the RCM  senses a short to ground on either passenger air bag stage 1 circuit, a fault will be indicated.
  B0010:12 - Passenger Frontal Stage 1 Deployment Control: Circuit Short to Battery	When the RCM  senses a short to voltage on either passenger air bag stage 1 circuit, a fault will be indicated.
  B0010:13 - Passenger Frontal Stage 1 Deployment Control: Circuit Open	When the RCM  measures greater than the desired resistance range between passenger air bag stage 1 circuits, a fault will be indicated.
  B0010:1A - Passenger Frontal Stage 1 Deployment Control: Circuit Resistance Below Threshold	When the RCM  measures less than the desired resistance range between passenger air bag stage 1 circuits, a fault will be indicated.

This pinpoint test is intended to diagnose the following: 

• Wiring, terminals or connectors
• Passenger air bag module
• RCM