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2002 Chevrolet Trailblazer LS 4.2L codes P1633, B1440
Posted to GM Driveability on 12/30/2004 7 Replies

Hi everyone. This TrailBlazer came in with service soon light, 4x4 light, and ABS light on. The VCM, ATC, BCM, and IPC all had a pile of 'loss of voltage' and communication codes. We replaced the ignition switch which fixed most of it. Were now left with P1633...

7 Replies Received (View Replies)

  Related Documents & Media  2002 Chevrolet Trailblazer LS

 
Message Closed w/FIX

car Vehicle Data

2002 Chevrolet Trailblazer LS

VIN 1GMDT13S42
Engine4.2 L / 6 cyl / GAS
Trans4-speed Automatic (Electronic)
DeliveryFI
EmissionsOBD-II Compliant
SymptomsCodes P1633, B1440
OccursIntermittently

Trouble Codes

B1440Ign 0 voltage loss to BCM
P1633TCM Internal - Test External Watchdog Performance
Message Closed w/FIX

car Vehicle Data

2002 Chevrolet Trailblazer LS

VIN 1GMDT13S42
Engine4.2 L / 6 cyl / GAS
Trans4-speed Automatic (Electronic)
DeliveryFI
EmissionsOBD-II Compliant
SymptomsCodes P1633, B1440
OccursIntermittently

Trouble Codes

B1440Ign 0 voltage loss to BCM
P1633TCM Internal - Test External Watchdog Performance