Dashboard Fuel Gauge

[Stan Simpson]

We got the coach out of storage last week, and I've spent the time getting "Da Coach" ready for our trip to Texas and beyond. Fuel gauge read a little over 1/4 so I added $100 of fuel, and when I restarted the engine, the fuel gauge pegged all the way to the right, and has stayed there. Today, I completely filled the tank, and there is no change.

I had this issue once before. Someone said it is probably a ground wire that is loose. The one on the side of the tank is impossible to access unless I crawl all the way under there, and I am just not comfortable doing that, especially when I am two miles from home at a storage lot by myself.

I have heard mention of a ground on the back of the dashboard as well. What would that look like, exactly? To see under there, I have to lie down with my legs stretched out almost halfway down the "hallway" in the living room, as I am 6-3. Then I have to squinch under the dash forcing my shoulders in to the space between the console and the steering column. I'd just like to know what to look for once I get wedged in there.

Thanks in advance for your help.

Stan

P.S. It would be so nice if the Aladdin had a fuel monitor. Does the Silverleaf have one?

[Steve Huber]

Stan,
Not sure about your 05 but the dash gauges in my 2000 and 2001 coaches both had threaded brass studs with ~3/8" nits to attache the wires. On the 01 I found a number of them loose, giving me flakey readings. May want to check there.
Steve

[Roy C Tyler]

 Not sure about your 05, but my 03 has several screws holding the dash in.  I just upgraded my dash radio and rather than crawl under, I removed the screws and slid the dash forward carefully. It was a lot easier working on it sitting in the Captains chair than on the floor on my back.

[Bob Stone]

Stan, I have the same coach as you, a '05 Laguna IV with the identical dash fuel gauge problem. The backside of the instrument cluster is easily accessed via the hatch on the top of the dash just above the gauges. This hatch is held tightly in place with Velcro - just pull on one edge and it will slowly release.

Unfortunately even after ensuring all connections were tight, including those that attach to a common bus bar the fuel gauge still only works when the tank is down to less than one quarter of capacity. Until that point it reads 'full'.

I too am afraid of crawling under the rig to check the connections at the tank, even if there was sufficient clearance to do so.

Being a boondocker, it is somewhat of a nuisance having to calculate the quantity of fuel remaining by recording the number of hours the generator and hydraHot have run since the last fill.

Good luck and I look forward to hearing your solution.

Bob Stone

[Stan Simpson]

Thank you Bob, I always wondered what that little rectangle was for. I will post my findings.

Stan

[Mark Bryant]

Stan, Bob
I have an 06 Monterey and had the same issue! After all the all the trouble shooting I ended up replacing the fuel probe!
I contacted Centroidproducts.com in Florida. The web site has trouble shooting info and e-mail for the tech, Joel. Now my fuel gage reads correct and it cost me less than $100 as I replaced the probe my self.

Mark

[Gerald Farris]

If the fuel gauge reads correctly from 1/4 tank or less , but shows full at any reading above 1/4 tank, there is at least a 95% chance that the problem is the fuel sending unit that is in the tank.

Gerald

[Stan Simpson]

If the fuel gauge reads correctly from 1/4 tank or less , but shows full at any reading above 1/4 tank, there is at least a 95% chance that the problem is the fuel sending unit that is in the tank.

Gerald

Thank you Gerald.

Would that be true even if the needle is pegged all the way to the right. I mean, if there was no glass, it would be at 5 o'clock! I'm guessing its going to be a pricey fix if that's the problem. Luckily, my sending unit (picture attached) is on the side of the tank.

Stan

[Steve Huber]

Stan,
I think the sending unit is effectively a variable resistor that changes resistance as the tank level changes. If you can get to the sending unit terminals in the photo easily with a meter you should be able to measure a resistance difference at different tank levels. If no change in resistance at various levels, the sending unit is probably bad.
Steve

[Gerald Farris]

Stan,
What you described is an open circuit condition at the fuel sending unit. Check the voltage and the ground at the unit, if they are good, the sender is open and you will get an infinite ohm reading across it with the hot wire removed. If so, replace the sending unit, but be careful that the fuel level is below the sending unit location before removing it.

Gerald

[Edward Buker]

Stan,

More than likely the fuel gauge wire connections are fine and I say that because the unit gave a proper reading when your fuel was low in the tank. That verifies the connections and the dash gauge. As you added fuel to the tank the gauge went to beyond full, which as Gerald points out indicates that the unit has an open. The sending unit in the tank has a flat wirewound element with a wiper connector on the float arm. That generates the variable resistance and voltage that is proportional to the amount of fuel in the tank. In your case the open in the wirewound element is somewhere above the 1/4 full tank point because your unit worked up until you added fuel. The "open" situation can be a worn or broken element wire or possibly a contact wiper arm that does not make good contact throughout the whole sweep. In either case the fix is to replace the sending unit. Hope this helps.

Later Ed

[Mark Bryant]

Stan
This is the web site I spoke about! They manufactured the fuel sender.
Mark

[Stan Simpson]

Thank you everyone for your input and suggestions. It looks like I will be replacing the sending unit.

Stan

[Stan Simpson]

Stan
This is the web site I spoke about! They manufactured the fuel sender.
Mark

Mark,

Thank you for this information. I have emailed them for information.

Stan

[Edward Buker]

Mark,

Are these units being capacitance driven compatible?

Later Ed