Instrument Cluster Repair

[Randy3282001]

I have a 1998 Monaco Windsor on Roadmaster chassis that we need the Gauge cluster repaired . Oil Pressure and Fuel . Any leads to a repair shop?

[Lowflyer1]

What engine do you have?
Have you already checked the oil pressure sender (or switch) and fuel sender.

These could be bad, or maybe just corroded terminal(s).

On many oil pressure applications the gage is actually operated by a switch, not a real sender.

[Randy3282001]

Originally Posted by Lowflyer1

What engine do you have?
Have you already checked the oil pressure sender (or switch) and fuel sender.

These could be bad, or maybe just corroded terminal(s).

On many oil pressure applications the gage is actually operated by a switch, not a real sender.

Thanks I started with the sending unit with no luck . I'm surprised how many shops work on instrument clusters just not RV

[Lowflyer1]

Can you clarify why you did not have luck with the sending units? Could not find them or could not analyze? If those are bad, trying to fix or swap clusters will not help.

Did both gages go inop at the same time, are they erratic etc.

I don't know your expertise in these areas so need more info.

[Randy3282001]

Originally Posted by Lowflyer1

Can you clarify why you did not have luck with the sending units? Could not find them or could not analyze? If those are bad, trying to fix or swap clusters will not help.

Did both gages go inop at the same time, are they erratic etc.

I don't know your expertise in these areas so need more info.

Thanks for great questions . I'm a soon to retire electrician/ jack of all trades .

The fuel gauge has always been inaccurate since I purchased RV . I have not attempted to find the sending unit for it . It may be a calibration issue.

I'm more concerned with not knowing oil pressure. It started with gauge bouncing all over the place and then quitting altogether . Replacing the sending unit did not change it.

I've attempted to use Scan Gauge as oil pressure reading with no luck. Scan Gauge worked with me by sending different cables with no luck .

$ 500.00 buys a used cluster up to $ 1500 for repair.

I appreciate your thoughts.

[RamiDav]

Randy, Before you spend a lot of money, these rigs seem to be plagued with ground
issues in the gauges. The grounds are supposedly daisy-chained in some manner
but can still develop a bad ground at each gauge.
I would investigate the grounds. Some ground blocks are under the dash and some
are outside on the firewall, cleaning and tightening might cure you issue.

I'm pretty sure I have a ground issue with my fuel gauge, it works until I turn the
lights on then it goes bonkers. I think it has a ground through the instrument bulbs
until they are turned on.

The fuel sending units go bad too, they are electronic, no float, and made by Centroid
The fuel sender is accessed through the pass side fuel door, the big panel that
doesn't open. It can be made to open by removing screws under the coach then it
will lift but will have to be proper up.

[Lowflyer1]

My 04 HR fuel sender access is the same as RamiDav described and I agree it's worth checking all the connections first.
The previous owner had replaced the fuel sender before I got it as it was reading full all the time. He got the sender from Veurink's RV Center. The new sender has no calibrations. If you end up replacing it, just mark/number the wires carefully as mine had 5 of them, skinny wires with pretty small screws.

With the sender off for another issue, I was able to see if there were any contaminants in the tank. I got a submersible flashlight as the opening is only like 1 1/2" and with a regular flashlight, all I saw was the reflection of the top of the tank.

For the oil pressure sender/switch, do you know if you got the correct replacement? A bad or wrong replacement sender would indicate the same bad info on the scan gauge.
In that era, there were quite a few changes in the automotive industry from actual senders to switch operated gages and electronics and they use the same systems in the RVs.
Do you have the Owner's manual, that should indicate what your rig has-switch or sender or a combo unit like mine has?
You could verify the oil pressure with an actual pressure gage, should vary anywhere from maybe 10-60 psi or more depending on rpm, temp etc.
In testing we used to T-off a pressure transducer so we could monitor the actual pressure changes for starts, maneuvers etc. and compare to gage indication.

[Randy3282001]

Originally Posted by RamiDav

Randy, Before you spend a lot of money, these rigs seem to be plagued with ground
issues in the gauges. The grounds are supposedly daisy-chained in some manner
but can still develop a bad ground at each gauge.
I would investigate the grounds. Some ground blocks are under the dash and some
are outside on the firewall, cleaning and tightening might cure you issue.

I'm pretty sure I have a ground issue with my fuel gauge, it works until I turn the
lights on then it goes bonkers. I think it has a ground through the instrument bulbs
until they are turned on.

The fuel sending units go bad too, they are electronic, no float, and made by Centroid
The fuel sender is accessed through the pass side fuel door, the big panel that
doesn't open. It can be made to open by removing screws under the coach then it
will lift but will have to be proper up.

Awesome I learned something today. I'll check out the fuel sending unit now that I know how to access.

Correct me if I am wrong with my thought process as it relates to the instrument cluster. The Instrument cluster is a PC board with edge connectors . Wouldn't there be a common ground for the whole board?
I did find the ground bar and checked all of the connections.

[Lowflyer1]

Originally Posted by Randy3282001

Awesome I learned something today. I'll check out the fuel sending unit now that I know how to access.

Correct me if I am wrong with my thought process as it relates to the instrument cluster. The Instrument cluster is a PC board with edge connectors . Wouldn't there be a common ground for the whole board?
I did find the ground bar and checked all of the connections.

Yes, it should have common ground although there may be several grounds coming in. Different suppliers have different approaches due to EMC, ground offsets and other considerations.
It's always possible that there is a break somewhere on the board in the traces or connections. Those may need a strong magnifying glass to detect. You may also need to twist the board to find any intermittent connections but that is a difficult, maybe impossible task to do in the vehicle.



So it's typically easier and cheaper to check the sensors and connections first.

[Randy3282001]

Originally Posted by Lowflyer1

Yes, it should have common ground although there may be several grounds coming in. Different suppliers have different approaches due to EMC, ground offsets and other considerations.
It's always possible that there is a break somewhere on the board in the traces or connections. Those may need a strong magnifying glass to detect. You may also need to twist the board to find any intermittent connections but that is a difficult, maybe impossible task to do in the vehicle.



So it's typically easier and cheaper to check the sensors and connections first.

Thanks Ill get my magnifying glass out . I appreciate all your help.

[Randy3282001]

Originally Posted by Lowflyer1

My 04 HR fuel sender access is the same as RamiDav described and I agree it's worth checking all the connections first.
The previous owner had replaced the fuel sender before I got it as it was reading full all the time. He got the sender from Veurink's RV Center. The new sender has no calibrations. If you end up replacing it, just mark/number the wires carefully as mine had 5 of them, skinny wires with pretty small screws.

With the sender off for another issue, I was able to see if there were any contaminants in the tank. I got a submersible flashlight as the opening is only like 1 1/2" and with a regular flashlight, all I saw was the reflection of the top of the tank.

For the oil pressure sender/switch, do you know if you got the correct replacement? A bad or wrong replacement sender would indicate the same bad info on the scan gauge.
In that era, there were quite a few changes in the automotive industry from actual senders to switch operated gages and electronics and they use the same systems in the RVs.
Do you have the Owner's manual, that should indicate what your rig has-switch or sender or a combo unit like mine has?
You could verify the oil pressure with an actual pressure gage, should vary anywhere from maybe 10-60 psi or more depending on rpm, temp etc.
In testing we used to T-off a pressure transducer so we could monitor the actual pressure changes for starts, maneuvers etc. and compare to gage indication.

Thanks I'll check it out