2000 TRX450ES Display Problems

[AdamP 1]

Hello, I recently purchased a 2000 Foreman 450ES and the red oil temp. light is always on and the odometer shows 418,000 miles 52,000 hours. Is there a fix for it? Thank you!

[Goober 1,555]

Yes please download the service manual in the forum folder labeled manuals.

 

you need to perform the oil cooling system diagnostics tests to check fan operation, sensor resistivity, fan control unit and wiring. 
 

usually when you switch on, the neutral light will come on steady and the oil light will come on momentarily and then go out.

 

an oil light that stays on without fan running indicates a failed fan control unit. If the sensor or wiring is shorted then the fan and oil light usually both come on. 
 

you could also have a failed fan so run the diagnostics—grounding the sensor lead you’ll see pretty quick if fan runs.

Edited May 10, 2022 by Goober

[Goober 1,555]

Seek the OEM parts finder at Rocky Mountain atv and Partzilla. They should have an FCU for your model. Pretty common for the temp sensors to be out of spec so you may want to get one of those as well.

[AdamP 1]

Thanks Goober, I will check a few things out and look into the FCU for the temp light. Any input on correcting the odometer/hour meter? New display?

 

[Goober 1,555]

The other members can guide you better on the display question. My thot is ES displays are no longer available unless you search the OEM part number on fleabay and get lucky. so if your quad runs and shifts, I’d be happy for now and get on with service items. @AKATV might be able to fix your display.

 

I’ve done the following on my early 450S—i think the ES is similar in the it has separate CDI and FCU:
 

Try this heating method to diagnose your FCU. Heat FCU, connector side up, in an oven 200F for 3 hours. Others have used a hair dryer. Slight heating can allow the circuitry to expand and reestablish a broken circuit. The oven trick might get you 3-6 months. Use contact cleaner, plumbers flux brushes and permatex dielectric grease to clean and lube the connectors and backshells before u reinstall 

To remove your FCU—there are two modules secured to the front of the frame with a rubber hanger. it’s the one on the driver’s left (sitting in seat). Connected to two subharnesses. Each connector has two ears—be patient and reach up in there with both hands—lightly pry the ears slightly outward with two fingers and push out on the subharness connector with your remaining digits.

 

if you can’t reach it you may have to remove the front fender

Edited May 11, 2022 by Goober

[AKATV 850]

Dont just warm up FCU- heat it up to 450 for 8 minutes and actually reflow the the internal solder joints 

The internal solder connections wont melt at 200 degrees and you will just end up doing it again

I have some still working properly for folks after reflowing the solder connections 15 years later

 

AdamP has messaged me for reprogramming his meter

 

 

[Fishfiles 20,147]

20 hours ago, AKATV said:

Dont just warm up FCU- heat it up to 450 for 8 minutes and actually reflow the the internal solder joints 

The internal solder connections wont melt at 200 degrees and you will just end up doing it again

I have some still working properly for folks after reflowing the solder connections 15 years later

 

AdamP has messaged me for reprogramming his meter

 

 

 

 

So , preheat the oven till it reaches 450F  ,  then stick in the FCU for 8 minutes ----  do you think that same time will work on CDIs , alarm boxes and control modulars 

[AKATV 850]

For sure, I have used it on CDI boxes

as well as the FCU (fan control unit) which is sometimes called an alarm box as well. 
I have found preheating the oven seems to work best and 8 minutes is ballpark, but has worked best over  the years 

Its a great last ditch try, as if its not working you have to get another one anyways

It doesn’t always work, but I have had a great success rate with many over the years maybe 75-80% or better 

its good to let it cool down without moving

It as well

its basically nothing but a circuit card covered in a bunch of epoxy and

after 20 years of heat and cold plus vibration, it will cause a crack in poor solder joints inside -that is why sometimes knocking on a CDI will get it to spark

Once you reflow the solder joints in the oven, it will take care of the intermittent connection- not every time, as there are other issues like component failures etc -but it’s definitely worth a shot

I usually put it facing plug side up on tinfoil or pie pan -best to do when wife is out shopping….it will make a plastic smell

Also,sometimes the old epoxy will split on the plug side of the box, its not an issue- just fill with epoxy or rtv

good luck!

 

 

 

 

Edited May 12, 2022 by AKATV

[Goober 1,555]

I haven’t tried the high temp/short duration heating. Like akatv said a last ditch effort, so instead of jumping into the high temp option, I’d like to recommend escalating in the following order so as to first properly diagnose the issue. 

1. remove the module and clean the contacts. Use contact cleaner and a plumber’s flux brush. Get all the dirt from inside and outside the connector. Inspect the subharness and module connectors for loose pins and exposed wires. Lube contacts and backshell with permatex dielectric grease. Reinstall and check operation.

2. Heat module with hair dryer. Reinstall while warm to see if the module is revived.

3. Heat in oven 200F for at least 3 hours. Connector side up. It will smell a bit but should not melt anything. Keep in mind oven temps vary due to controller heating cycles. Ovens set at 200F frequently cycle from 180F to 220F. Let cool completely before you reinstall. I got six months out of my FCUs this way so now I know the higher temp might offer a permanent solution.

4. Bake in oven at 450F for xx minutes on the middle rack?. 5-7 might do it.

 

Edited May 12, 2022 by Goober

[Fishfiles 20,147]

Maybe this repair should be in the Food Channel thread ,   COL