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Signal description, Transmission Control Module (TCM)

All values contained below are between the terminal in column 1 and #A53 (signal ground), unless otherwise indicated in brackets.

NOTE:

It is important to connect the breakout box and check ground terminals before taking readings.

U = DC voltage in volts (V) UAC = AC voltage in volts (V)
Ubat = battery voltage f = frequency in Hertz (Hz)
Ulow = voltage approximately 0 V %duty = duty cycle (pulse ratio) as a percentage (%)
t = time in milliseconds (ms)    
Connector A #A35 - #A70

Breakout box terminal  Control module terminal  Signal type  Ignition on  Engine idling  Other 
#A35 #A35 Power supply Ubat Supply from fuse 16 in the integrated relay/fusebox in the engine compartment
#A37 #A37 Signal, oil temperature sensor Cold transmission (+20°C): U=2.4 V
Hot transmission (+100°C): U=0.3-0.5 V
U decreases with increasing temperature
#A39 #A39 Signal, vehicle speed sensor (VSS) Tooth against sensor: 14 mA
Cover against sensor: 7 mA
The sensor generates a pulsed signal (quadratic wave) with fixed pulse ratio when the pulse wheel rotates. Frequency increases with speed
#A41 #A41 Signal, transmission speed sensor Tooth against sensor: 14 mA
Cover against sensor: 7 mA
The sensor generates a pulsed signal (quadratic wave) with fixed pulse ratio when the pulse wheel rotates. Frequency increases with speed
#A45 #A45 Signal, gear-shift position sensor C Gear selector position D, 3, L: U=0-0.5 V
Other positions: U=0-2 V below Ubat
Signal grounded in positions D, 3, L
#46 #A46 Signal, gear-shift position sensor A Gear selector position P, R, 3, L: U=0-0.5 V
Other positions: U=0-2 V below Ubat
Signal grounded in positions N, D
#A50 #A50 Control signal, shift solenoid S1 Activated: U=0-2 V below Ubat
Not activated: Ulow
The solenoid receives a signal when activated by the transmission control module (TCM) it is in 2nd and 3rd gears
#A51 #A51 Control signal, lock up solenoid SL Activated: U=0-2 V below Ubat
Not activated: Ulow
The solenoid receives voltage when it is activated by the transmission control module (TCM)
#A52 #A52 Control signal, line pressure solenoid STH U=1.6 V Voltage decreases with increasing throttle opening
#A53 #A53 Signal ground (SG) Ulow -
#A55 #A55 Signal ground oil temperature sensor (OTG) Ulow Ground
#A57 #A57 Power supply, vehicle speed sensor (VSS) U≈1 V -
#A59 #A59 Power supply, engine speed (RPM) sensor U≈1 V -
#B3 #A63 Signal, gear-shift position sensor PA Gear selector position P, N, 3: U=0-0.5 V
Other positions: U=0-2 V below Ubat
Signal grounded in positions P, N, 3
#B4 #A64 Signal, gear-shift position sensor B Gear selector position R, N, D, 3, L: U=0-0.5 V
Other positions: U=0-2 V below Ubat
Signal grounded in positions R, N, D, 3
#B8 #A68 Control signal, shift solenoid S2 Activated: U=0-2 V below Ubat
Not activated: Ulow
The solenoid receives voltage when activated by the transmission control module (TCM) in 1st and 2nd gears
#B10 #A70 Signal ground, line pressure solenoid STH f=300 Hz Frequency is constant, independent of driving conditions. The signal duty cycle is modified when line pressure is adapted -
Connector B #B1 - #B22

Breakout box terminal  Control module terminal  Signal type  Ignition on  Engine idling  Other 
#B11 #B1 Communication cable control modules (Control area network(CAN)) 2-3 V Between transmission control module (TCM) and engine control module (ECM)
#B12 #B2 Communication cable control modules (Control area network(CAN)) 2-3 V Between transmission control module (TCM) and ABS control unit and also central electronic module (CEM)
#B23 #B13 Communication cable control modules (Control area network(CAN)) 2-3 V Between transmission control module (TCM) and engine control module (ECM)
#B24 #B14 Communication cable control modules (Control area network(CAN)) 2-3 V Between transmission control module (TCM) and ABS control unit and also central electronic module (CEM)
#B31 #B21 Communication cable
VULCANO light
- Between transmission control module (TCM) and gear selector module (GSM)
#B32 #B22 Diagnosis cable K-link - -