2005 Gauges not working flashing ECU
I have a 2005 prostar 205 v and the gauges are not working. They try wiggle when I first turn the key on but that is it. The digital display on gauges is working and is flashing ECU.
Here is where I am at with my trouble shooting so far:
Have used the boat about a dozen times with gauges not working and boat runs great, but I want to fix this annoying problem.
Have fully charged batteries (boat dual battery set up) and clean connections. Have checked voltage under dash it does match voltage reading at battery. Have check ground block and even temporary tied it in to both bat. neg post (did not help).
Took it by dealer and they checked MMDC, ECU (with code computer), some new gauges, fuses, and the relays. With two service techs and myself trouble shooting we could not find the problem. Only the digital readout works giving lake and water temps and the infamous "ECU". I have checked, checked, checked and rechecked the voltage difference at the ground block and the problem does not appear to be there unless one of the ground wires has a short in it.
Also, I checked voltage at back of one of the gauges and it is getting power –6.5v from the MMDC.
That is what I have. I have unplugged them all gauges and even tried a new gauge from local MC dealer. Also, found out the 4 wires on my boat are as follows:
orange: 6.5v power from mmdc
yellow: CAN_MMDC --- this wire is digital feed
Back: Ground ___ All my gauges appear to have good ground
Blue: power for lights
From CAN MMCD OUT Harness (what Mastercraft calls the harness, not MMDC) I have 12v at pin E (from battery) and 12 volt at pin F when ignition is on. Problem does not appear to be here.
Also checked the ground at pin D and it has a good ground. I plugged the out harness back in and checked voltage at gauges. I checked ground first and it was good. I also tied a wire back to the ground block to ensure a good ground. I checked the oil pressure gauge since it was on the end and the easiest one to get to. I had 6.5 volts (gauge power to it from pin B) at the gauge, but the control wire seems to be the problem. I am not sure what the voltage should be here.
Also, I traced the two CAN (digital wires the provide all the interments with info) on the MMCD-IN Harness to the ECU. My problem does not appear to be a bad between the MMDC and ECU.
I am scratching my head on what to do next. I will post some pictures that might help other out.
Please give all suggestions. I am planning to take boat back to dealer in few weeks if I can figure it out, but don’t want to throw give up yet.