No gauges

folivier · 07-16-2010, 12:20 AM

I went out to run the coach today. No gauges! Here is a list of what is not working:
RPM, Oil press, Water temp, Engine volts, Fuel Tach, Fuel gauge (neither main or aux.), Also the Check Engine and Stop Engine lights don't flash when turn on ignition.
Also in the rear electrical panel in passenger side engine compartment there are two breakers for the DDEC power. I reset both of them, but only one worked. It looked like the one closest to the engine would not reset. The engine would only run about 300 rpm and was blowing black smoke. I replaced that breaker with a 20amp auto-reset breaker and now the engine starts and seems to run ok.
VMSpc does receive info from the computer so I'm getting water temp, engine volts, rpm, oil press, turbo boost.
But I still don't have any gauges! Can't see any wires loose or connectors loose. Funny that they all stopped working at the same time.
Any ideas?

express1 · 07-16-2010, 01:53 AM

What gauges do you need? Sounds like VMS has them covered!!

folivier · 07-16-2010, 02:00 AM

I just like things to work. I'm wondering if there is a main ground wire (or even power wire) that I might have knocked loose when I was changing one of the indicator lights? Are there any fuses for these gauges?

prairieschooner · 07-16-2010, 02:56 AM

I would always start the Ground Wire, it should be easy to check. OK find a Hot Wire (12 Volts DC +) and a Ground (12 Volts DC -). Now check from the Hot to the Ground at the Gauges and then reverse the check and check the Ground to the 12 Volts DC (+) at the Gauges. If the readings are questionable you need run the wires from the Engine Battery to the Gauge Panel just to be sure. This problem sounds like a voltage problem rather than a Sending Unit, to test a Sending Unit you can ground the Sensor Wire for a SHORT PERIOD of time and the Gauge should peg (just make sure that you don't connect the sensor to ground and then lallygag!!!)
Our '82 has Fuses under the Glove Box area.

folivier · 07-16-2010, 04:09 AM

Steve, I'm thinking it may be a ground issue also. Seems weird that all of these gauges would go out at the same time. Of course I did have my fat fingers behind the dashboard trying to troubleshoot the speedometer and also changing out an indicator light for the merge switch. I'll spend some time checking out the ground first. Thanks if it works you just earned a bowl of gumbo!

folivier · 07-16-2010, 02:23 PM

Sometimes it pays to sleep on a problem. Started this morning with a game plan, all of the gauges lights came on with headlights. All gauges had a good ground. With ignition on I had NO 12v to any of the gauges! I know that I checked out the fuses yesterday at least twice. But today I found fuse #15 (ignition gauges) was blown! Replaced it and gauges work, except for the speedo which I'm still trying to figure out.
I guess when I changed out the burnt indicator light for the merge switch my fat fumble fingers shorted something out to burn the fuse!
Steve, you just earned a bowl of gumbo!

prairieschooner · 07-16-2010, 03:14 PM

yum yum!
fuel to get gumbo $1,200.00, rv park bill $80.00, Cindy's Gumbo..priceless!

if it is any consolation, I was advising you from experience.

folivier · 07-16-2010, 03:26 PM

I spoke too soon, on second look the engine voltmeter is not working. Guess I'll be looking at that this weekend. At least this latest fiasco found that bad breaker for the DDEC computer! A lot easier changing that out at home rather than the side of the road!

Richard and Rhonda · 07-18-2010, 03:31 AM

Forrest,

Sorry to be late to the game, but start with the obvious, which you did after sleeping on it.

I would look first in the area that you were working to see what you might have shorted or knocked loose. The grounds on my gauges are daisy chained, so if you lose one you lose many.

There also may be more than one fuse.

Good luck.