Dead Gauges - 00 Supra Launch

[Launchman2000]

I bought this boat last month and all the gauges except water temp do not work. The gauges do light up and the hour meter inside the tach works. I didn't think it was any big deal since I got a good deal but the boat mechanic is a little puzzled, he said the gauges all tie into a central black box, does that sound like the culprit here? I am out of town now, not much I can do but I can pass on any info to him. Thanks for any help.

[TX skier]

I don't know if this will help but... I have a 1999 Santera that the gauges come and go. I went behind panel and unplugged them one at a time. I got to the tach, and the rest came to life. I called Medallion Instrument and just need to order a new tach.

Hope this helps.

David

[Launchman2000]

Thks, I'll pass it on, he may not have tried that yet.

Hal

[PoPz]

This could sound dumb, but trust me in my case it made a big difference with gauge problems, try cleaning every connection, to the gauges and where they connect to the ignition and where they connect to the fuse panel and where they eventually connect to the different parts of the engine i.e. ignition coil, alternator, etc etc..

It may do nothing, but it may fix your problems. Boat connections get beat up, crusty and wiggle lose in transit on the trailer and when getting tossed around on the rough water..

That black box is probably the alarm and it could also be a culprit.

[Launchman2000]

Well I finally got my boat out on the water and all gauges work correctly now except fuel tank and speedo. Speedo is not that big of deal since an iphone and GPS work fine. I suspect I need a new sending unit for the fuel tank level. I topped it off before I got out on the water and it pretty much stays on empty the whole time. The little black box was about $350 from Medallion Instruments. Thanks for the suggestions.

[docdrs]

did you put in a new mdc unit?

[Launchman2000]

Yes I think that is what it is, flat rectangular box in the dash where all the gauges tie in. The boat mechanic I used was not that experienced with supra boats.

[bobbyT]

Welcome to the club...year 2000! I bought a Legacy 2000 this summer and the gauges were not functioning. Love the boat and the sellers disclosed the problem openly and I was aware of the issue. I will attach the link from a discussion had in 06 about this same issue. I did not attempt to resolve the issue because the extra time I had was spent on the lake and enjoying the sweet boat! Unfortunately it made for some challenges with disconnected gauges (speed and fuel). So here is what I have and I will be working on this project soon (hopefullY)

https://forum.supraboats.com/showthr...0+supra+legacy

To order the control unit for the gages give medallion a call at 616-847-3700. They are based out of spring lake MI. The control unit is around $300.

Launchman2000, did you install one of these control units? Or just look into them?
I am considering putting in the new unit and not attaching the speedos (see above link). Some suggested using a handheld GPS for accurate speed and no more gauge problems. Do all GPS' read accurate speeds? Any inexpensive speedo GPS suggestions?

So, any expereinced boaters that have enjoyed the 2000s can help us both out.

Just took the boat and dock out for the year

[docdrs]

I had a 99 moomba outback and replaced mine after about 5 years....the problem is with the speedo lines. moisture/water would get up into the unit , freeze and eventually crack the housing and water illl get right into the unit.
You have to disconnect these lines during winterization to prevent this....some say even remove the mdc unit and store it inside your home.....fyi

[td in nc]

I just purchased a 2000 Supra Launch which I am making a list of repairs. Top on the list is getting the gauges working. The temperature, oil pressure and gas gauge do not work. The speedo and tach work. After reading this and other threads, it is unclear to me if the control unit is bad, would the speedo and tach still work? I will chase all the grounds and connections this weekend, but do not want to waste my time as it sounds like the control units had some real issues. The previous owner said the gauges only worked for him a few months after he bought it 4 years ago, he chased the connections and ground, but never found anything.

I hope to post a pic of boat soon. Currently have a 85 Ski Nautique 2001 which we have outgrown.