Pinpoint Test S: No Communication With The RCM

WARNING: This page is about a different car, the 2005 Ford Pickup, 2005 Ford F550 Super Duty, 2005 Ford F450 Super Duty, and 2005 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Most faults are due to connector and/or wiring concerns. Carry out a thorough Inspection and Verification before proceeding with the Pinpoint Test.

S1 CHECK THE RCM CONNECTOR C2041 AND CONNECTOR PIN 5 FOR DAMAGE
WARNING: Restraint system diagnostic tools are for service only. Tools must be removed prior to operating the vehicle over the road. Failure to remove restraint system diagnostic tools could result in injury and possible violation of vehicle safety standards.

WARNING: Never probe the connectors on the air bag module. Doing so can result in air bag deployment, which can result in personal injury.

NOTE: After diagnosing or repairing a supplemental restraint system (SRS), the restraint system diagnostic tools must be removed before operating the vehicle over the road.

NOTE: The SRS must be fully operational and free of faults before releasing the vehicle to the customer.
- Key in OFF position.
- Depower the system. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING in this article.
- Disconnect: RCM C2041.
- Inspect RCM C2041, harness side and RCM C2041, component side, pin 5 for damage.
- Are RCM C2041 and RCM C2041 pin 5 OK?
- Yes : GO to S2.
- No : REPAIR RCM C2041 or RCM C2041 pin 5 as necessary. RECONNECT the system. If previously directed to deactivate the system, REACTIVATE the system. REFER to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEACTIVATION AND REACTIVATION in this article. REPOWER the system. REFER to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING in this article. PROVE OUT the system. CLEAR all DTCs.
S2 CHECK THE DLC CONNECTOR C227 AND CONNECTOR PIN 7 FOR DAMAGE
- Inspect DLC C251 and DLC C251 pin 7 for damage.
- Are DLC C251 and DLC C251 pin 7 OK?
- Yes : GO to S3.
- No : REPAIR DLC C251 or DLC C251 pin 7 as necessary. RECONNECT the system. If previously directed to deactivate the system, REACTIVATE the system. REFER to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEACTIVATION AND REACTIVATION in this article. REPOWER the system. REFER to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING in this article. PROVE OUT the system. CLEAR all DTCs.
S3 CHECK CIRCUIT 609 (OG/YE) FOR AN OPEN
- Deactivate the system. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEACTIVATION AND REACTIVATION in this article.
- Key in ON position.
- Measure the voltage between RCM C2041 pin 2, circuit 609 (OG/YE), harness side and ground; and between RCM C2041 pin 13, circuit 609 (OG/YE), harness side and ground.
  
  Fig 1: Measuring Voltage Between RCM C2041 Pin 2, Circuit 609 Harness Side And Ground; And Between RCM C2041 Pin 13, Circuit 609 Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts?
- Yes : GO to S4.
- No : REPAIR circuit 609 (OG/YE). RECONNECT the system. If previously directed to deactivate the system, REACTIVATE the system. REFER to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEACTIVATION AND REACTIVATION in this article. REPOWER the system. REFER to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING in this article. PROVE OUT the system. CLEAR all DTCs.
S4 CHECK CIRCUIT 649 (BK/OG) FOR AN OPEN
- Key in OFF position.
- Measure the resistance between RCM C2041 pin 21, circuit 649 (BK/OG), harness side and ground.
  
  Fig 2: Measuring Resistance Between RCM C2041 Pin 21, Circuit 649 (BK/OG), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 0.5 ohm?
- Yes : GO to S5.
- No : REPAIR circuit 649 (BK/OG). RECONNECT the system. If previously directed to deactivate the system, REACTIVATE the system. REFER to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEACTIVATION AND REACTIVATION in this article. REPOWER the system. REFER to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING in this article. PROVE OUT the system. CLEAR all DTCs.
S5 CHECK CIRCUIT 70 (LB/WH) FOR AN OPEN
- Measure the resistance between RCM C2041 pin 5, circuit 70 (LB/WH), harness side and DLC C251 pin 7, circuit 70 (LB/WH), harness side.
  
  Fig 3: Measuring Resistance Between RCM C2041 Pin 5, Circuit 70 (LB/WH), Harness Side And DLC C251 Pin 7 Circuit 70
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes : GO to S6.
- No : REPAIR circuit 70 (LB/WH). RECONNECT the system. If previously directed to deactivate the system, REACTIVATE the system. REFER to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEACTIVATION AND REACTIVATION in this article. REPOWER the system. REFER to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING in this article. PROVE OUT the system. CLEAR all DTCs.
S6 CONFIRM THE RCM FAULT
NOTE: Make sure all restraint system diagnostic tools, sensor electrical connectors and the RCM electrical connector are connected before carrying out the on-demand self test. If not, erroneous DTCs will be recorded.
- Connect: RCM C2041.
- Reactivate the system. Do not prove out the system at this time. Refer to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEACTIVATION AND REACTIVATION in this article.
- Enter the following diagnostic mode on the diagnostic tool: On-Demand Self Test.
- Did the diagnostic tool communicate with the RCM?
- Yes : Fault corrected. RECONNECT the system. If previously directed to deactivate the system, REACTIVATE the system. REFER to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEACTIVATION AND REACTIVATION in this article. REPOWER the system. REFER to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING in this article. PROVE OUT the system. CLEAR all DTCs
- No : INSTALL and CONFIGURE a new RCM. RECONNECT the system. If previously directed to deactivate the system, REACTIVATE the system. REFER to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEACTIVATION AND REACTIVATION in this article. REPOWER the system. REFER to SUPPLEMENTAL RESTRAINT SYSTEM (SRS) DEPOWERING AND REPOWERING in this article. PROVE OUT the system. CLEAR all DTCs.
  CHECK for causes of the intermittent fault. ATTEMPT to recreate the hard fault by flexing the wire harness and cycling the ignition key frequently. ACTIVATE other systems in the same wire harness. REPAIR any intermittent concerns found.