This post will explain how to hook up your PC to the ECU of a Hisun/Coleman/Etc UTV to be able to read error codes & engine parameters for troubleshooting purposes.
This is applicable to all small engines using the Delphi MT-05 ECU. This should cover all fuel injected Hisun models, as well as various other Chinese FI engines, as the Delphi MT-05 ECU seems to be the favored ECU solution.
Even though we get actual engine error codes to display on the dash, sometimes we have “pending codes” (not yet confirmed by the ECU) or other intermittent issues that are hard to diagnose, for example a poorly connected sensor that may give intermittent false readings, or a sensor that’s putting out bad date, but not bad enough for the ECU to realize.
The setup requires 2 cables, which are available for around $25 combined, a PC with a USB port, and some charityware software called “HUD ECU Hacker”. This gives the same functionality as the $300 dealer code scanner for a fraction of the price.
In searching I found info about HUD ECU Hacker, but I have yet to see info anywhere about how to hook it up to a Hisun, so I took the leap and bought some cables, and made it work. I will show a step by step of how to do so in post two.
I will be breaking this down into 2 posts:
Delphi ECU Info & Overview (This post) System setup & use Delphi ECU Info (Skip ahead to the next post if your eyes glaze over technical details)
The Delphi MT-05 ECU was developed to allow small engines to use fuel injection. A fuel injection system requires feedback from various sensors to operate efficiently. This feedback allows the adjustment of ignition timing, fuel injection volume, etc to efficiently and cleanly produce the most power possible from a given engine.
The MT-05 ECU has a number of sensors that are required for proper functioning including; Coolant temp, crankshaft position, intake temp, intake pressure, exhaust O2, throttle position, as well as some other optional sensors that are used on more complex vehicles.
From the sensors the ECU adjusts: Fuel injector timing/pulse, Idle air control valve, and ignition coil
The Delphi MT-05 puts out diagnostic data, however it is not ODB2 like a modern car, where is where it gets tricky reading it. There are three options, there is an old 16 bit piece of software Delphi has that is not able to run on a modern computer, there is the motorscanner tool for dealers ($300), or there is freeware HUD ECU Hacker with the proper cables.
By Tim Barbero
I left my 2020 axis 500 UTV parked under the carport for about 6 months and when I went to start it recently a squirrel has built a nest under the throttle body and chewed through the efi harness. I stripped all the wires back and reconnected them with waterproof butt connectors. The problem I have is there is one blue wire with a red stripe coming from the main harness this wire has 5 volts dc showing on my multimeter but there are two blue wires with a red stripe coming from 2 different sensors on the throttle body. I looked through all of the bits and pieces of wiring left behind and there’s no indication that the three wires of the same color were all tied together. Any help with this issue would be greatly appreciated.
After a few days of heavy rainfall I got in my Sidekick and noticed that the belt seemed to be slipping as I was making my way out on a large property. I turned around and could barely make it back to my shop. After removing the cowelling I noticed about a quart of water drained out. I dried the area, the cover and checked the belt. No signs of dammage, belt looks great and no foreign debris other than water in the area. I put it back together and there was a definite improvement. The Sidekick is driveable now but the belt still slips but only at a higher speed and only when the throttle is punched. I'm wondering whether I may have inadvertently damaged it while it was wet and have ordered a new belt. I have looked on line to see if there is a guide or procedure, specifically for the CVT belt removal and replacement for the 850 but can find none. Does anyone have experience with this?