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

Pinout Values and Diagnostic Parameters

ABS/TCS MU/CM INSPECTION





1. Disconnect the negative battery cable.
2. Connect the SST between the ABS/TCS MU/CM and harness connector with the ignition switch off.
3. Attach the tester leads to the SST and inspect voltage.

Terminal Voltage Table (Reference)








(Engine is idling, and connector is connected unless otherwise indicated)

Inspection Using An Oscilloscope (Reference) Wheel speed





^ ABS/TCS MU/CM terminal:
RR: A(+)-B(-)
LR: C(+)-F(-)
RF: G(+)-D(-)
LF: I(+)-E(-)
^ Oscilloscope setting: 1 V/DIV (Y), 2 ms/DIV (X), AC range
^ Vehicle condition: Driving 30 km/in (18.6 mph)

Note:
^ As vehicle speed increases, the wave period shortens.
^ If there is malfunctioning in the sensor rotor, the wave profile warps.

Vehicle speed output





^ ABS/TCS MU/CM terminal: V( + )-AC ( - )
^ Oscilloscope setting: 1 WDIV (Y), 5 ms/DIV (X), DC range
^ Vehicle condition: Driving 30 km/in (18.6 mph)

Note: As vehicle speed increases, the wave period shortens.