tank monitoring level system inop

[deckmaster50]

monitoring system doesnt work to check levels of tanks was working ok but now nothing checked power at all other switches for fan,light,and water pump on same panel above stove in 99 damon intruder 349 any help will be appreciated

[RV Wizard]

Welcome to iV2.com. We are glad to have you join us. I am sure you will enjoy this website and forums. Check for a broken common wire; usually white that is the ground plane for the sensors.

[deckmaster50]

thanks mike, we check ground. I think the light panel is bad dont know where to find.

[RV Wizard]

Give Damon a call for part.

[wa8yxm]

The sensor system

The panel has a power and ground connection.. The bottom sensor on the tank is also grounded, MAY or may not be grounded via the panel ground (No reason to do it that way but who knows)

Panel----{wire}------(F)---/\/\/--(2/3)---/\/\/---(1/3)

I am showinga "3 sensor" type, some are 1/4, 1/2, 3/4 F

/\/\/ is a resistor

The resistors are inside an epoxy "Chip" which is likely wrapped in tape Wires from each sensor go to this chip and then one goes off to the panel

Testing.. 2 person job

Have partner inside talk to you via cell or 2-way radio

Take a jumper wire (Any length of wire will do, helps if it has a clip on at least one end) and hook it first to the bottom (Ground) sensor, this is the one sensor NOT hooked to the aformentioned chip

Other end of wire to known ground (Chassis) and have partner check.. WORKS, bad ground, sensor fix the ground

IF still no work then touch the FULL sensor.. WORKS, bad sensors (Nearly zero percentage posibility but the test only took a second)

Now, find the wire going to the panel, expose the wire and touch it, FULL TANK, bad chip (More common but still rare)

Now seal the exposed part of the wire (GOOP works well) and go inside.. Take your jumper with you

Open panel and find the sensor wire.. Test at that point, WORKS, if shorting the wire to ground (use panel ground) works you have a broken wire or bad connection

Suspects include the crimp on splices where the panel's tiny wires hook to much larger wire used in the motor home.. I had to re-do several of those in my house.