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B2172



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PINPOINT TEST 5: DTC B2172 - INERTIA FUEL SHUTOFF (IFS) SWITCH INPUT CIRCUIT OPEN - HYBRID

Normal Operation

With the engine running, the battery power off (BPO) function may be triggered by the front and/or rear inertia fuel shut off (IFS) switches opening, a high-voltage interlock circuit opening, the electrical interlock (EL I) circuit opening (fuse protected by the battery junction box [BJB] fuse 26 [5A]) or if the contactor box within the traction battery control module (BCM) requests a BPO mode. If the IFS switch opens and causes the BPO mode to occur, no DTCs are set. Also, if the IFS switch is open, a power reset indicator in the instrument cluster illuminates. With the ignition switch in the ON position and the engine on or off (the engine must have run at least once after the key was cycled to ON), the BCM monitors the contactors continuously. During a power down (key OFF) sequence, one or both of the contactors may set this DTC if they fail.

- DTC B2172 (IFS Switch Input Circuit Open) - If the BCM detects that the IFS switch circuit(s) is open, the DTC is set.

Possible Causes
- IFS switches
- Wiring, terminals or connectors
- High-voltage traction battery (HVTB)

Diagnostic Procedure

Step 1-Step 4:





Step 5: