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Drivetrain - Encoder Motor Damage If Run Off Vehicle

Group Ref.: Transmission
Bulletin No.: 367403
Date: February, 1994

SUBJECT:
TRANSFER CASE ENCODER MOTOR DAMAGE WHEN ACTIVATED OFF VEHICLE

MODELS:
1992-94 CHEVROLET AND GMC T TRUCKS EQUIPPED WITH NP 233 ELECTRIC SHIFT TRANSFER CASE (RPO NP1)

If the encoder motor is energized or activated when it is not attached to the transfer case, the shift motor internal to the encoder will not have a positive stop and damage to the internal gears may result.

To prevent damage, do not energize or activate the encoder motor when it is not properly attached to the transfer case. For diagnosis of the transfer case, refer to Section 7D TRANSFER CASE in the appropriate S/T Service Manual, Diagnosis of the Transfer Case.