Speedometer pegged to max

[windsorbill06]

Nope, I'm not driving that fast.   Speedometer is pegged at max.  Engine on, off, doesn't matter.  When I turn key on, needle doesn't seem to move or twitch.  All other gauges are working as they should.   

I did have an alternator issue and I think got an electrical spike.  This pegged needle seems to have happened about that time frame.  That alternator issue has been resolved.

I've tried the obvious, taping on gauge, unplugging it from behind and playing with the trip/odometer button, nada.  

I believe its a Beede gauge.     I see NW Supply carries what I think is replacement, if I need to go that route.

 

Anyone know of a reset?  or other ideas?

[Notn2bars]

Bill, there should be a pot on the back of the speedo.  When mine was acting up, I marked the setting on the pot and took a small screw driver,  turned the pot back and forth a couple of times.  Then reset it to the original setting.  It has worked great ever since.  Just a thought!! God Bless, Ed & Sylvia

[Harvey Babb]

Is the odometer advancing too or just the speed indication?

 

[windsorbill06]

31 minutes ago, We2dynasty said:

Bill, there should be a pot on the back of the speedo.  When mine was acting up, I marked the setting on the pot and took a small screw driver,  turned the pot back and forth a couple of times.  Then reset it to the original setting.  It has worked great ever since.  Just a thought!! God Bless, Ed & Sylvia

Ed,

I didn't see a pot on the back, but I was looking from the small dash access opening.  It's real tight and alot of wires.  I did see it has a bunch of DIP switches, but haven't touched those.

I might pull the gauge out of the dash and see if there is anything visible to adjust.

 

26 minutes ago, Harvey Babb said:

Is the odometer advancing too or just the speed indication?

 

I haven't driven the coach since this has acted up just a few days ago.  I hope to take it out in next day or so and see if the odometer is working.  I was actually hoping that  might get the needle to start working again, (hopeful, I know) and I'll report back the odometer functions as well.

Edited June 20, 2022 by windsorbill06

[Alan Penniman]

I'm not sure on the motorhome, but I know that Chevy Silverado's are known for the electric motors in the gauges to go south.  That happened in mine, where the speedo wouldn't go down, just up and then would go up on top of what was already wrong and getting maxed out.  They sell the motors for the Chevy's.  Wonder if you can do the same here.  It does mean taking the gauges apart and soldering to make the replacement. 

 

[windsorbill06]

I did take coach out for a short drive.  Speedometer still pegged at max.  The odometer is working and seems accurate.  All other gauges seem to be working normally.

[Tom Cherry]

Two suggestions….from both a MH owner and a ne’er do well electronics fixer.

Pots or Potentiometers are notoriously cantankerous as they age.  I am NOT a an expert on the MH speedometer.  Since the Odometer works, the issue is probably in the POT or internal to the speedometer.  Exercising or moving a stuck or malfunctioning Pot will often work.  You MIGHT disconnect the Chassis Battery and let it sit for a few minutes or such.  The good thing about that, your Transmission Control Module will reset and you then drive it normally like you would and it then, in a short time, is fresh and not had any bad habits.  We have had members that had to pay an Allison tech to do that as the tranny started shifting “not like before”….so this IS a proven TECH RECOMMENDED” fix.

Second,,,,while the power is off…..do a little “thumping” with a screwdriver handle.  Medium sized and NOT a 4 pound ball peen hammer 🔨.  If there is a mechanical issue, you might have fixed it. 

As to the POT, I will defer to,others….but somewhere I thought it was actually a “multiposition” switch….  So make sure you get it BACK exactly to the Monaco setting.  Flexing or exercising might clean away the pad.  At a LAST resort….a tiny shot of ELECTRONIC contact cleaner (NOT ELECTRICAL…as they are stronger) might work.  Or a good shot of Canned Computer Air to dislodge anything.

My thoughts and those with more experience should chime in and correct if there are glaring errors in my advice.

Let us KNOW what fixes it or the progress…

 

[windsorbill06]

Tom

Thanks for the ideas.    

If anyone here has a gauge that looks similar to the one I posted earlier, I wonder if you can open up your dash access port and take a picture of the DIP switch positions??  

I have 12 DIP switches on the back side of the speedometer.  It's possible (but NOT likely) that I hit one of them when I was digging in there to access the plug and back of the instrument.

[cbr046]

On my 2002 F53 chassis the tachometer would stick at full RPM when the key was turned to start about 1 / 3 times.  It eventually became a game that involved salt, chanting and sacrificial chickens.  After a few hundred miles mysteriously the tach would jump to normal RPM.  I drilled a small hole in the lens so I could nudge it back with a paper clip wire.  That wasn't a fix, but it would jump to normal operation quicker.  ALL THAT SAID, I don't think that's your problem. 

You might try a vibrating tool and apply it to the dash near the speedo. 

Both these ideas are a shot in the dark.  If I could have gotten the instrument cluster out of the F53 I would have taken a completely different approach.

Good luck,

- bob

[Larry Laursen]

I lost the dash gauges on my unit while traveling last year and again this year.  A 10 amp. fuse blew in the Monaco box 2 that is labeled dash/fuel sender.  So, I had no gauges for fuel, speed, tach, oil pressure, cruise on light, etc.  The wire also goes back to the alternator, as best as I can tell, and was shorted to ground.  Last year I moved and tied off the wire and everything was fixed with a new fuse.  This year the same thing happened with the speedometer pegged full. I have run a plastic sheath over the wire to eliminate the short, fingers crossed.  The dash is working except the speedometer is pegged at max.  I will be moving tomorrow so will see if it works then.  I can't remember if the speedometer was pegged last year, but it worked after the fix.

I doubt that the DIP switches were moved.  The speedometer may have a power or ground issue. 

[Harvey Babb]

After considerable thought and reading all the posts here my belief is that the most likely problem is either the failure of the electronics or (as suggested by Alan Penniman above) the stepping motor that moves the indicating needle.

I have had a stepping motor failure in my 2005 Chevy Venture, and that was an obvious mechanical failure that happened over a period of weeks rather than instant total failure. 

Given the coincidence of the alternator problem mentioned in the original post I'd lean toward the failure of the electronics being the actual cause.

At any rate, I think you are down to getting a replacement.

 

[windsorbill06]

Larry,

The nut on one of the small wires on the back of the alternator had split and 1/2 of the nut fell off.  The other half was still threaded on the stud BUT the wire wasn't tight to the post.  That loose wire kept blowing the 10 amp fuse in the "MONACO 2" box up front, which controls all the dash gauges.   Once I traced that split nut problem, gauges were all fine except the speedo.  I think there must have been a spike that 'sapped' the speedometer needle to MAX.

I just tried using a very strong magnet and I was able to pull the speedometer needle from its resting spot at MAX, back down to zero. Sounds to simple to  me, but it worked.    I test drove it and it seems to be working as usual.  

If yours keeps acting up, you might try the magnet trick to pull the needle around.

 

11 minutes ago, Harvey Babb said:

After considerable thought and reading all the posts here my belief is that the most likely problem is either the failure of the electronics or (as suggested by Alan Penniman above) the stepping motor that moves the indicating needle.

I have had a stepping motor failure in my 2005 Chevy Venture, and that was an obvious mechanical failure that happened over a period of weeks rather than instant total failure. 

Given the coincidence of the alternator problem mentioned in the original post I'd lean toward the failure of the electronics being the actual cause.

At any rate, I think you are down to getting a replacement.

 

You're a faster typer  than me! 

 

I got it resolved.  I was pretty well prepared to get the new gauge.  Would have ordered one, but that model is discontinued.   Can't find it anywhere.    I was getting ready to call mfg to try to get a replacement model number, when I tried the magnet trick--kinda 'hail mary' move.    Was a long journey to get to that point of using a magnet to drag the needle around.  Hope it helps someone down the road.

Edited June 21, 2022 by windsorbill06

[Larry Laursen]

Bill,

"I got it resolved.  I was pretty well prepared to get the new gauge.  Would have ordered one, but that model is discontinued.   Can't find it anywhere.    I was getting ready to call mfg to try to get a replacement model number, when I tried the magnet trick--kinda 'hail mary' move.    Was a long journey to get to that point of using a magnet to drag the needle around.  Hope it helps someone down the road."

 

I have a strong magnet.  Was wondering where you placed the magnet.  On the speedometer face at the end of the needle and then just bring it around to zero?

[windsorbill06]

larry,

 

my magnets are about the diameter of a quarter and about 3x as thick.  And I have a bunch of them stacked together--kinda like a long sausage.    I just grabbed the entire stack and put it near the needle, maybe midway.   Then gently and slowly pulled the needle around to zero.  The first time I did it,  I moved the magnetic too fast and the needle just went back to MAX.

It kinda of reminded me of the old days when we had those 'etch-a-sketch' toys where you would take a magnetic pencil and drag the metal fillings to make different designs, but you couldn't pull it real fast.

[Notn2bars]

Bill, good news that you were able to get your speedo issues resolved.  God Bless, Ed & Sylvia

[Larry Laursen]

Just an  update, I put a plastic sheath on the wire. Everything looked good but the speedometer was pegged.  After driving at 60+ for a few miles the speedometer worked. 

[windsorbill06]

3 hours ago, Larry Laursen said:

Just an  update, I put a plastic sheath on the wire. Everything looked good but the speedometer was pegged.  After driving at 60+ for a few miles the speedometer worked. 

Interesting it self fixed itself.   I never got up to highway speed during my test drive, so unless it happens again, I'll never know if that would have worked for me.

 

Glad you got it working again.

Edited June 23, 2022 by windsorbill06