Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

Test A: The PCM Does Not Respond To The Scan Tool

PINPOINT TEST A: THE PCM DOES NOT RESPOND TO THE SCAN TOOL


A1-A2:






A2-A3:






A4:






Normal Operation
The PCM communicates with the scan tool through the high speed controller area network (HS-CAN). Circuits VDB04 (WH/BU) (HS-CAN +) and VDB05 (WH) (HS-CAN -) provide the network connection to the PCM. The PCM shares the HS-CAN network with the ABS module, the restraints control module (RCM), the occupant classification sensor module, the four wheel drive (4WD) control module (if equipped), the adaptive front lighting module (if equipped), the steering angle sensor module (if equipped) and the instrument cluster.

This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- PCM