MUT
Overview of MUT
The Mitsubishi Multi-Use Tester, or "MUT" is a handheld diagnostic and test unit specific to Mitsubishi vehicles and used used by dealerships.
Prior to EvoScan, MUT was the only method of obtaining real-time data from the ECU. Prices for MUT units are extremely high, so most end users rely on tools like EvoScan to provide similar information, when coupled with an OpenPort 1.3 or OpenPort 2.0 adapter.
Protocol
The MUT Protocol is proprietary, but has been reverse engineered by the developers of EvoScan. It is a relatively slow protocol, with a maximum data rate of 15,625 baud (roughly 15 kilobits per second). Communication is based off ISO9141, but without the L-Line. (K-Line only). It is a Bi-directional protocol, allowing for data to be sent to and from the system or module it is communicating with.
Initialisation
Five-baud init on ISO9141 Kline
Pass byte to initialise which system to communicate with
| Address | System that will respond |
|---|---|
| 0x0 | Engine Control Unit |
| 0x1 | Transmission Control Unit |
| 0x89 | Immobiliser (not applicable to VR-4) |
| 0x92 | SS4II (not applicable to VR-4) |
| 0x85 | TCL |
| 0x2 | ECS |
| 0x4 | ABS |
| 0x83 | Steering (not applicable to VR-4) |
| 0x91 | HBB (not applicable to VR-4) |
| 0xB | AYC |
| 0x8 | SRS |
| 0x8A | SWS (??? vr4 thought might use) |
| 0x19 | TPMS (not applicable to VR-4) |
| 0x1A | CAMERA (not applicable to VR-4) |
Communication
After initialisation, 1-byte PIDs are sent, and a 1byte response is received.
To make sense of the response, a scaling is applied to make the value human readable.
List of PIDs here: https://www.ozvr4.com/wiki/index.php/MUT_Requests
There are also commands that can be sent to operate actuators for diagnosis
list of PIDs here:https://www.ozvr4.com/wiki/index.php/MUT_Commands
if data is not kept active, then reinitialization is required.