Mercedes TCM programming solutions


Transmission control module (TCM) is found in latest Euro 6 Mercedes MP4 truck models. Control unit is a part of MB SFTP truck electronic system and is responsible for fluent automatic gearbox work.

There are 3 different types of TCM’s:

- Festo
- Wabco
- Bosch

How to determine one from another?

Festo TCM has the most visual differences from other two types of TCM. Bosch and Wabco, from the first look, looks pretty much the same, but you can notice little hardware differences when you know where to look.

Pictures below will help you determine, which TCM you have:







Replacing TCM

It’s a common case, that TCM gets faulty and needs to be repaired or replaced. Most of the technicians would rather choose to replace the TCM to save time and get the truck back on the road asap.

If you buy second hand TCM, control unit is already paired to another truck. To replace, you need to do unpairing with Truck Explorer, so that TCM becomes virgin. Then you can put it inside your truck and make pairing with MCM and EIS.

Full article on how to replace TCM

Although it’s an efficient solution for technicians, but some of the TCM’s cannot be unpaired…

New Truck Explorer features

AutoVEI has a solution to TCM modules that cannot be unpaired! Newest Truck Explorer release will allow you to read/write full flash & eeprom of all TCM versions (Wabco, Festo, Bosch). If your TCM cannot be unpaired, you can read your old faulty TCM and clone it with new one.

Read/write operations can be done in 3 different modes:
- OBD
- DC
- JTAG (only Wabco TCM models)

EMERGENCY NOTE: Bosch and FESTO TCM versions do not have JTAG connection. Wrong dump or unexpected abort of operation can damage ECU. Use read/write functions at your own risk!

Video tutorial how to read/write TCM by DC2. No need to open control unit. Works with Festo, Wabco, Bosch.

Video tutorial how to read/write TCM by JTAG mode. Need to open control unit. Works only with Wabco TCM models.

Truck Explorer supports:

1. Bosch TCM:
FLASH: MPC5566 (3072 KB)
EEPROM: 95640  (8KB)
DC/OBD mode. No JTAG mode

2. Wabco TCM:
FLASH: MPC5644 (4096KB)
EEPROM: 95640  (8KB)
DC/OBD/JTAG mode

3. Festo TCM:
FLASH: TC1799 (3072 KB+64KB)
EEPROM: 95640  (8KB)
DC/OBD mode. No JTAG mode

Requirements to work with TCM:
- VEI V6/V7 device
- Direct Connect 2U tool with OBD2 power cable
- DC2-TCM cable
- DC2U-ISP-JTAG+BDM dongle (for JTAG)
- DC2U-JTAG8 open flex (for dongle)
- Power supply
- License MB TCM
- Truck Explorer Software v6.20 or greater