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Home >> Mazda >> 2008 >> B4000 Base, Automatic >> Repair and Diagnosis (Single Page) >> Restraints >> Restraints Control Systems >> Symptom Troubleshooting [Restraints] >> Pinpoint Test 17: DTC C1946 - Front Driver's Seat Track Position Switch Circuit Open >> Normal Operation
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Normal Operation

The restraints control module (RCM) monitors the driver seat track position sensor circuits. If the RCM detects an open circuit, it will store DTC C1946 in memory and send a message to the instrument cluster module to illuminate the air bag warning indicator. If the RCM detects an open on the driver seat track position sensor circuit, it sets DTC C1946 Front Driver's Seat Track Position Switch Circuit Open.

This pinpoint test is intended to diagnose the following: 

WARNING:
  • Remove restraint system diagnostic tools from the vehicle prior to road testing. If tools are not removed, the supplemental restraint system (SRS) device may not deploy in a crash. Failure to follow this instruction may result in serious personal injury or death in a crash and possibly violate vehicle safety standards.
WARNING:
  • Never probe the electrical connectors on safety belt buckle/retractor pretensioners or adaptive load limiting retractors. Failure to follow this instruction may result in the accidental deployment of the safety belt pretensioners or adaptive load limiting retractors, which increases the risk of serious personal injury or death.
CAUTION:
  • Use the correct probe adapter(s) when taking measurements. Failure to use the correct probe adapter(s) may damage the connector.
NOTE:
  • The SRS must be fully operational and free of faults before releasing the vehicle to the customer.
NOTE:
  • Supplemental restraint system (SRS) components should only be disconnected or reconnected when instructed to do so within a pinpoint test step. Failure to follow this instruction may result in incorrect diagnosis of the SRS.
NOTE:
  • Most faults are due to connector and/or wiring concerns. Carry out a thorough Inspection and Verification before proceeding with the Pinpoint Test.
DIAGNOSIS PROCEDURE - FRONT DRIVER'S SEAT TRACK POSITION SWITCH CIRCUIT OPEN

PINPOINT TEST 17 DTC C1946 - FRONT DRIVER'S SEAT TRACK POSITION SWITCH CIRCUIT OPEN
STEP INSPECTION ACTION
1 CHECK FOR AN INTERMITTENT AND ON-DEMAND DTCs
  • Enter the following diagnostic mode on Integrated Diagnostic System (IDS) or equivalent tester:

    RCM Self Test/Retrieve and Record On-Demand and Continuous Memory DTCs

  • Was on-demand DTC C1946 retrieved? 
 Yes This is a hard fault. The fault condition is still present. This fault cannot be cleared until it is corrected and the DTC is no longer retrieved during the on-demand self-test. Go to next step.
No This is an intermittent fault when present as a continuous memory DTC only (DTC not retrieved on demand). The fault condition is not present at this time. Go to step 6.
2 CHECK CIRCUIT (Y/V) FOR AN OPEN BETWEEN THE RCM AND DRIVER SEAT
  • Key in OFF position.
  • Depower the SRS. See DEPOWERING AND REPOWERING .
  • Disconnect: RCM connectors 0810-101b and 0810-101a.
  • Disconnect: Seat Track Position Sensor connector 0810-112.
  • Measure the resistance between RCM connector 0810-101 a pin 23, circuit (Y/V), harness side and driver seat track position sensor connector 0810-112 pin 2, circuit (Y/V).
  • Is the resistance less than 0.5 ohm? 
 Yes Go to next step.
No REPAIR circuit (Y/V). Go to step 7.
3 CHECK CIRCUIT (B/L) FOR AN OPEN TO GROUND
  • Measure the resistance between driver seat track position sensor connector 0810-112 pin 1, circuit (B/L) and ground.
  • Is the resistance less than 0.5 ohm? 
 Yes Go to next step.
No REPAIR circuit (B/L). Go to step 7.
4 CHECK THE SEAT TRACK POSITION SENSOR
  • Connect: RCM connectors 0810-101b and 0810-101 a.
  • Install a known good driver seat track position sensor.
  • Repower the SRS. Do not  prove out the SRS at this time. See DEPOWERING AND REPOWERING .
  • Enter the following diagnostic mode on IDS or equivalent tester:

    RCM Self Test/Retrieve and Record On-Demand and Continuous Memory DTCs

  • Was on-demand DTC C1946 retrieved? 
 Yes Go to next step.
No Fault corrected. Go to step 7.
5 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.

  • Key in OFF position.
  • Depower the SRS. See DEPOWERING AND REPOWERING .
  • Reinstall the original seat track position sensor.
  • Repower the SRS. Do not  prove out the SRS at this time. See DEPOWERING AND REPOWERING .
  • Enter the following diagnostic mode on IDS or equivalent tester:

    RCM Self Test/Retrieve and Record On-Demand and Continuous Memory DTCs

  • Was on-demand DTC C1946 retrieved? 
 Yes INSTALL a new RCM. See RESTRAINTS CONTROL MODULE (RCM) . Go to step 7.
No CHECK for causes of the intermittent fault. ATTEMPT to recreate the hard fault by flexing the wire harness and cycling the ignition key frequently. Do not install any new SRS components at this time. SRS components should only be installed when directed to do so in the pinpoint test.  REPAIR any intermittent concerns found. Go to step 7.
6 CHECK FOR AN INTERMITTENT FAULT
  • Key in OFF position.
  • Enter the following diagnostic mode on IDS or equivalent tester:

    RCM Self Test/Retrieve and Record On-Demand and Continuous Memory DTCs

  • Was on-demand DTCC1946 retrieved? 
 Yes This is a hard fault. The fault condition is now present. This fault cannot be cleared until it is corrected and the DTC is no longer retrieved during the on-demand self-test. Go to step 2.
No CHECK for causes of the intermittent fault. ATTEMPT to recreate the hard fault by flexing the wire harness and cycling the ignition key frequently. Do not install any new SRS components at this time. SRS components should only be installed when directed to do so in the pinpoint test.  REPAIR any intermittent concerns found. Go to next step.
7 CHECK FOR ADDITIONAL SRS DTCs
WARNING:
  • Turn the ignition OFF and wait one minute to deplete the backup power supply. Failure to follow this instruction may result in serious personal injury or death in the event of an accidental deployment.

  • Reconnect all SRS components (If previously, disconnected).
  • If previously directed to depower the SRS, repower the SRS. Do not  prove out the SRS at this time. See DEPOWERING AND REPOWERING .
  • Enter the following diagnostic mode on IDS or equivalent tester:

    Self Test/Retrieve and Record RCM On-Demand and Continuous Memory DTCs

  • Enter the following diagnostic mode on IDS or equivalent tester:

    Clear all RCM/OCSM Continuous Memory DTCs

  • Enter the following diagnostic mode on IDS or equivalent tester:

    Self Test/RCM

  • Are any RCM DTCs retrieved indicating a fault? 
 Yes Do not clear any DTCs until all DTCs have been resolved. See DIAGNOSTIC TROUBLE CODE (DTC) INDEX - RESTRAINTS CONTROL MODULE (RCM)  for pinpoint test direction.
No PROVE OUT the SRS. REPAIR is complete. RETURN the vehicle to the customer.
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