I checked the manual and it states to stop and check all fluids. the coolant is ok , the oil level is ok, the oil pressure is at 60 at idle the coolant is 190 degrees. the transmission shifts alright I need to locate the dip stick for the transmission. I think it is a malfunctioning sensor. I drove it home 600 miles sometimes after a stop it would come on sometimes it did not light up nothing seems out of the ordinary? except the light is on the air pressure stays around 120 pounds and does not leak down when the engine is off HELP

Does the manual state the name of the light? Is is a malfunction indicator light or check engine light? If it's not named in the guide can you describe the light or take a picture and post it?

Have you checked the differential pressure indicator on the air filter ?My Roadtex computer threw a transmission over temp code on our trip back from Texas. Next fuel stop I checked the fluid level and it was way low. added 4 Its fluid, reset the fault codes in the computer, has been OK since.

After filling up with fuel one night and, upon starting engine, a stop engine light came on immediately. Checked around coach and then proceeded to campground nearby. The next morning upon start-up the light had disappeared. I was a little hesitant to get on the road to my destination, and proceeded with some caution. Didn't have any further concerns. Never have had that again. Good luck with yours.

What transmission do you have. If you have the 3000 or better, you can check the transmission fluid with the shift selector pad. The manual says it is more accurate than the dipstick. The transmission has to be warmed up to do it. Just hold the up and down buttons at the same time. It will give a code indicating the level. The exact instructions will be in the allison manual that came with the rv. If you have the 2500 series or less, this feature is not available.

Please post what engine tranny combo you have. Also, let us know what you mean by a warning light. On mine the red light comes on accompanied by a loud 'ding'. As it flashes, it says why. i.e. check engine, fluids, water in fuel etc. If it's just a warning light with no indicator I can see where that would be irritating as well as disconcerting....Dennis

Warning Light on 2002 Monaco Diplomat | Good Sam Community

tomgagne
Explorer
Jun 26, 2019
Have you determined what the problem was?
Big_Katuna
Explorer II
Jun 16, 2019
Does it have a maintenance port?

Buy the Silverleaf software and cable. Connect to your laptop and read codes live while driving down the road.

Their techs will help you too.
tomgagne
Explorer
Jun 16, 2019
Cummins Engine codes

More information from irv2

Depending on how your dash switches are set up this may help you. Basically the warning is telling you the is an out of range condition from 1 of the many sensors on the engine. I had a similar problem and was able to determine the problem and replaced a grounded out sensor.

The diagnostic codes for the ISC and ISL: ISL & ISC Codes List- Cummins ECM

To bring up active codes, use the following, which I copied from another forum:

First, look on the dash where you will find two switches. One switch is to increase/decrease engine idle speed and the other is the Check Engine Diagnostic switch.

Now, turn the ignition switch to run - DON"T START - and press the engine diagnostic switch and hold it. Now the CHECK ENG and STOP ENG lights will flash the error code and you can determine what the code is from the table.

Example the amber CHECK ENG light will flash once the red STOP ENG light will flash out the error code. For error code 123, the CHECK ENG light will flash once, followed by the STOP ENG light flashing as follows -- FLASH pause FLASH FLASH pause FLASH FLASH FLASH -- then the CHECK ENG light will flash once and the cycle will repeat.

If you have more than one error code press the IDLE INCREASE switch to
go to the next error code. ALL Inactive codes will not display. If you any inactive codes, you will need the INSITE computer to reset them All inactive codes will only show a solidly lit CHECK ENG and STOP ENG light.

Good luck
slickest1
Explorer
Jun 15, 2019
On my previous coach I had that same light that says warning come on a couple times. I had the codes read and it turned out to be my Caps Fuel pump was having problems. Yours may be different but I think that warning light warns of low levels of fluids or a code being stored.
2chiefsRus
Explorer
Jun 13, 2019
devildog1971 wrote:
it is the allison transmission and cummins diesel
Which allison and which cummins?
devildog1971
Explorer
Jun 13, 2019
it is a "warning" light
devildog1971
Explorer
Jun 13, 2019
it is the allison transmission and cummins diesel
Executive45
Explorer III
Jun 11, 2019
Please post what engine tranny combo you have. Also, let us know what you mean by a warning light. On mine the red light comes on accompanied by a loud 'ding'. As it flashes, it says why. i.e. check engine, fluids, water in fuel etc. If it's just a warning light with no indicator I can see where that would be irritating as well as disconcerting....Dennis
winniman
Explorer II
Jun 11, 2019
What transmission do you have. If you have the 3000 or better, you can check the transmission fluid with the shift selector pad. The manual says it is more accurate than the dipstick. The transmission has to be warmed up to do it. Just hold the up and down buttons at the same time. It will give a code indicating the level. The exact instructions will be in the allison manual that came with the rv. If you have the 2500 series or less, this feature is not available.
faucet1
Explorer
Jun 11, 2019
After filling up with fuel one night and, upon starting engine, a stop engine light came on immediately. Checked around coach and then proceeded to campground nearby. The next morning upon start-up the light had disappeared. I was a little hesitant to get on the road to my destination, and proceeded with some caution. Didn't have any further concerns. Never have had that again. Good luck with yours.