Introduction

This guide provides details on setting up a COMPUSHIFT Sport or COMPUSHIFT Pro to an Link G4+ ECU.

These two systems are connected together using CAN bus, and signals like throttle position and engine speed are automatically transferred between the two units. No other connection is required.

Wiring Instructions

The CAN bus wiring kit supplied by HGM has two flying leads that must be crimped to the Link G4+ ECU connector pins and inserted into the appropriate position in the connector.

  • CAN high is the tan/black wire on the CAN harness.

  • CAN low is the tan wire on the CAN harness.

  • Once these are in place, the T connector and terminator portion the harness may be connected to the gray CAN connector on the COMPUSHIFT controller.

  • Ensure that both units are powered by the same switched ignition power so that they power on at the same time.

Setup Instructions

THESE SETUP INSTRUCTIONS ARE PRELIMINARY ONLY AND ARE NOT TO BE USED WITHOUT PRIOR AUTHORIZATION AND CONSULTATION WITH HGM AUTOMOTIVE ELECTRONICS.

In the PCLink software, connect to your ECU and go to the ECU Controls menu. From there, select the “CAN Setup” option.

This will bring up the CAN setup window. From there, select the “Streams” tab. In the streams tab, choose a stream that is unused. In this example, we are using Stream 3.

Add a single frame to this stream, which will be automatically named “Frame 1”. To this frame, add three parameters as shown:

The parameters are as follows:

Parameter

Start Position

Width

Byte Order

Type

Multiplier

Divider

Offset

TPS (Main)

8

8

MS First

Unsigned

1

10

125

Engine Speed

31

16

LS First

Unsigned

8

1

0

TPS (Main)

16

8

MS First

Unsigned

1

10

125

Note that TPS may be referred to as TP in the PCLink software, depending on the version you are using.

Once you have completed the stream setup, then you must add the stream to a CAN channel. Choose the CAN module the COMPUSHIFT is connected to (usually CAN 1 as shown below), and set the CAN Mode to “User Defined” and the bit rate to “1 Mbit/s”. In the “Data” section of the window, choose an unused data channel, and set the channel mode to “Transmit User Stream”, using the stream number you used in the previous section (our example used 3). Set CAN ID to “15729664” and the CAN ID format to “Extended”. The transmit rate must be set to 50 Hz. The screen show below shows the example settings:

From the COMPUSHIFT Setup app, be sure that the Vehicle Setup / Engine Type is set to J1939 Gasoline Engine:

and that the Network Setup / CAN Bus 1 Baud Rate is set to 1000 kb.

This should establish communication between the two systems.

Confirming Setup

  • Power cycle both controllers and start the engine.

  • Navigate to the dashboard on the setup app or handheld display of the COMPUSHIFT controller.

  • Confirm that the engine speed and throttle position are reading correctly on the display.

  • Confirm that there are no trouble codes on the COMPUSHIFT controller.

  • If any codes are present, do not drive the vehicle until the problem is resolved. Otherwise, you may damage your transmission.

You can diagnose CAN bus problems by going to Diagnostics / Network Diagnostics on the CS Setup App.
CAN 1 Receive Count should be steadily increasing when the ECU’s are communicating correctly.
The error counts should always be 0.