View Full Version : Temp gage

05-12-2003, 08:53 AM
Hey all,

Have a question. I have a 1999 Moomba Mobius. Late last year the temp gage started not working. What it is doing is as soon as the switch is cut on it pegs out at 240 degree or the max on the gage. This is right off the trailer without the engine running.

Was wondering if this is the gage or the sending unit. If it is the sending unit or the gage how do I get a new one or where can I buy on?


Brian Raymond
05-12-2003, 10:59 PM
Viper, locate the brass sending unit on top of the intake manifold or next to the thermostat housing. If it is fuel injected you will have 2 sending units, in either case the one that goes to the gauge has a single brown wire on it. With the key in the on pos. (not running) disconnect the brown wire from the sending unit, if the temp. gauge drops to 0, you probably have a faulty sending unit, and should be replaced by ordering through your dealer or Indmar for correct O.E.M. replacment parts. If the gauge is still pegged after disconnecting, trace the brown wire through the harness to verify it is not grounding out on anything. If all the above is done to no prevail, and your boat is equipped with the Kysor/Medallion dash package, call your dealer with your hull #, date of purchase, and the bar graph code number on the MDC box located at the stbd. transom corner of the boat behind th carpeted panel. Let me know what you find. Brian Raymond

05-13-2003, 07:37 AM
Thanks Brian,

I had already checked to make sure it was getting a good connection. Hadn't taken it loose yet. Will give that a try and see what happens.

Have a great day.


06-25-2003, 11:40 AM
It is very inportant that the black box (MDC) has a good ground and power to work correctly. There is a connector under the dash that is labled "to gauges" in that connector is a red and black that runs to the MDC. I would recommend cutting those wires and running them to the battery. That will clear up most the problems the MDC will have. If the gauge still reads high it is possable the MDC is bad.

05-23-2006, 01:29 PM
Well tried all of the things suggested and nothing work. Guess I will need to get a new computer. THe only gage not working is the temp gage. Oh well.

Thanks for the help.