DTC B2858-12

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DTC B2858-12 : Driver's E-Pretensioner Motor Circuit Short to Power

NOTE:

Before doing this troubleshooting procedure, review General Troubleshooting Information .
Before replacing the E-pretensioner unit, check the E-pretensioner unit software version with the HDS. If the software version is not the latest, update the E-pretensioner unit software , and retest.

DTC Description	DTC
B2858-12 Driver's E-Pretensioner Motor Circuit Short to Power

DTC (E-pretensioner)

Problem verification

-1. Clear the DTCs with the HDS.

-2. Turn the vehicle to the ON mode.

-3. Check for DTCs with the HDS.

DTC Description	DTC
B2858-12 Driver's E-Pretensioner Motor Circuit Short to Power

Is DTC B2858-12 indicated?

YES

The failure is duplicated. Go to step 2.

Intermittent failure, the system is OK at this time. Refer to intermittent failures troubleshooting.

Shorted wire check (E-PT L MTR+ line to power)

-1. Turn the vehicle to the OFF (LOCK) mode.

-2. Disconnect the following connector.

E-pretensioner unit connector A (16P)

-3. Turn the vehicle to the ON mode.

-4. Measure the voltage between test points 1 and 2.

Test condition	Vehicle ON mode
Test condition	E-pretensioner unit connector A (16P): disconnected
Test circuit	E-PT L MTR+
Test point 1	E-pretensioner unit connector A (16P) No. 2 (LT BLU)
Test point 2	Body ground

Courtesy of HONDA, U.S.A., INC.

Is there 3.9 V or more?

YES

Repair a short to power in the wire between the E-pretensioner unit connector A (16P) of the E-pretensioner unit and the driver's E-pretensioner motor.

The E-PT L MTR+ wire is OK. Replace the E-pretensioner unit .