Transmission control module, TCM, AF 40 (502b), E39
Transmission control module, TCM, AF 40 (502b), E39 |
Location |
TCM is mounted on top of gearbox.
Main task |
To control shifting points, system pressure and engagement of lock-up.
Type |
Micro processor with integrated Hall sensor.
Connection |
TCM is mounted directly on top of the gearbox. The gear selector is integrated in the control module. TCM is mounted so that the gear selector shaft goes through the control module. The position of the gear selector is calibrated with Tech 2 but there is no mechanical adjustment.
On the bottom of the control module is a 22-pole connector that connects directly to the gearbox. The TCM terminates to all the gearbox solenoids and sensors here.
Note | ||
The gear selector position sensor can sustain interference from magnetic fields such as magnetic pickup tools and high current cables, e.g. starter cables or wires to auxiliary equipment. |
The TCM has a micro processor. Adaptive values are stored in a non-volatile memory. When changing the gearbox, these values should be reset with Tech 2. After changing the TCM, the values will reset automatically when the new control module is added in the "Add" menu in Tech 2.
Power supply, ground and bus communication
Terminating with the electrical system in the car:Pin No. | Interface | Description |
9 | Grounding point G1 | Power supply |
11, 12 | +15 | Power supply |
1 | BATT+ | Power supply |
7 | P-bus + | Signal to/from other control modules |
6 | P-bus - | Signal to/from other control modules |
8 | P-bus + | Signal to/from other control modules |
14 | P-bus - | Signal to/from other control modules |
5 | Signal | Connected to control module, E39, pin 58(B). |
TCM termination directly to gearbox:
Pin No. | Interface | Description |
1 | SLT | Ground |
2 | S2 | Power supply+ |
3 | SLT | Power supply+ |
4 | SLU | Ground |
5 | S1 | Power supply+ |
7 | Temperature sensor | Ground |
8 | Temperature sensor | Temperature signal |
9 | SLU | Power supply+ |
10 | SLC1 | Ground |
11 | SLC1 | Power supply+ |
12 | Input shaft speed | Engine speed signal |
13 | Input shaft speed | Ground |
14 | SLC3 | Power supply+ |
16 | SLB1 | Ground |
17 | SLC2 | Power supply+ |
18 | SLC2 | Ground |
19 | Output shaft speed | Engine speed signal |
20 | Output shaft speed | Ground |
21 | SLB1 | Power supply+ |
22 | SLC3 | Ground |
Important | ||
When handling the control module, it is important first to create a ground connection between yourself and for example the vehicle engine. Avoid touching the pins of the control module. |
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