On_the_road

If you are getting a steady fuzzy picture, the problem is unlikely to be in the wiring. More likely is that the camera lens is dirty or water has gotten in the camera. By a "steady" picture, I mean one that is not jumping around or has problems when you flex the cable.

I have decided to get to the bottom of the problem with my oil pressure gauge. I cut it open using my lathe and a lathe bit ground very narrow. I wanted to cut a very narrow groove almost all the way through, leaving just a thin section that I could easily break. Here is the result; The steel can just slides off; The meter is a moving iron movement. That means that there are no hair springs like used in mechanical watches. There are two coils that are wound at right angles from one another. One coil is from the G (ground) terminal to the S (sensor) terminal and measures 175 ohms. The other coil is from the I (12 volt) terminal to the S terminal and measures 71 ohms. The movement is very rugged and cannot be damaged by applying 12 volts improperly. I tested the meter by connecting a potentiometer between S and G. When I turned the potentiometer to 0 ohms, the pointer moved to 0 PSI. When the potentiometer was set to 190 ohms, the meter went to 120 PSI. Here, the potentiometer is set to 100 ohms. Thus, my pressure meter is working correctly. I used aluminum foil tape to close the meter back up. It will seal the casing against dust and should be thin enough to fit back in the dash. If the tape does not work out, I will use glue. The original problem was that the meter was pegged at the maximum PSI. It did not move with the key on or off. The reason for this is in the nature of the meter movement. Without a hair spring, there is nothing to move the pointer when the power is off, it stays in the last position When the power is on, the pointer will peg due to the 12 volts unless a sensor is connected. The normal range for the pressure sensor is 0 ohms to 190 ohms. When the engine is stopped, there is no oil pressure and 0 ohms, so the pointer will move to 0 PSI. Therefore, my problem is not with the meter. Either the pressure sensor is bad or the wire going to the sensor is broken. Now I will have to chase that down.

I think that I found exactly what I want. https://www.wixroyd.com/en/catalog/access-components/catches-draw-latches/draw-latches/draw-latches-adj.-draw-secondary-lock/j0582/g+m+c+s+a It has the snap lock on the release handle to prevent it from opening inadvertently. McMaster has them; https://www.mcmaster.com/toggle-latches/adjustable-grip-draw-latches-with-safety-catch/ Kipp also makes something similar; https://www.kipp.com/gb/en/Products/Operating-parts-standard-elements/Latches/K0049-Adjustable-latches-with-concealed-screw-on-holes.html Thanks, Pete.

Thanks for the help. I ordered some of the switches. I was not sure what the latches were called, but with the suggestions I have found some that are similar but not the exact item. I will keep looking. Thanks, Pete.

The door on my water tank compartment has two latched and one is broken. I would like to replace the broken latch. They look like this: The basement doors have a switch, but some of them are broken. I would like to replace them, but I don't know what they are called. They look like this: Thanks; Pete.

I have been sorting out the wiring of my 2002 Monaco Signature. While working on the dash wiring, I noticed that my oil pressure gauge was pegged. It stayed pegged with the engine on or off, with no voltage to the meter. I can believe that I must have done something to cause this. This did work so it is probably my screw-up. Front: Back: Are these meters repairable? There is no manufacturer name that I can see. I have looked online for a replacement, but the gold bezel is not common. Thanks, Pete.

---------------------------------------- The ones that you see on the home tanks, I think, are really "Pressure Gauges". ------------------------------------------- The standard way to measure the fill percent of a propane tank is with a float. The pressure will stay about the same from full to empty as long as there is some liquid. Normally, a propane tank contains liquid at the bottom and the rest is filled with vapor. The pressure will vary with temperature. With rising temperature, some of the liquid boils and becomes vapor, thereby increasing the pressure and lowering the liquid level. The float will not give a precise measurement, but it is pretty good for most purposes. To get a precise reading, the float gauge needs to be compensated for temperature. Also, typical float mechanisms are really cheaply made.

The only purpose of the adjustment on these type movement meters is to set the zero. With no voltage or current on them, use the adjustment to set the pointer to zero. That is all that you can do. If the current reading is wrong, then the meter (or something else) is defective. The calibration is done in the factory and cannot be easily changed. Also, these type of meters are no more than 5% accurate.

I have seen lots of worn out relays over the years, both DC and AC. This particular failure is unusual. Mostly the contact surfaces wear down, sometimes very unevenly, but not with a hole blown in a contact surface that was otherwise in good shape. The metal from the hole then formed a single particle that got wedged between the contacts. The other common relay failure mode is for the contacts to weld together. I suspect that the contact had a crack in the silver from when it was manufactured. Likely, the crack occurred during the riveting process.

I have been chasing a problem with my remote lock/unlock system. Perhaps one in ten times the driver side lock fuse would blow. All the other 9 times it worked OK. Today I figured I would chase the problem down. It turned out to be the Bosch relay that controlled the unlock circuit. Looking at the schematic, it seemed unlikely to that a relay could cause the fuse to blow. I unplugged all the lock actuator motors in the basement doors, leaving only the relay and the wires as possible sources of the problem. But the failure persisted. Here is what I found: This is the bad relay, a genuine Bosch! There is a piece of metal wedged between the contacts. The relay still worked 9 out of 10 times in this condition. The reason the fuse would blow is that the normally open contact is connected to 12 volts and the normally closed contact is connected to ground. When the fuse would blow, the particle must have shifted such that the normally open and normally closed contact would both connect to the armature, resulting in a dead short and a blown fuse. I have pointed to the metal particle. This shows the contact of the armature with a hole in its surface. I have pointed to the actual metal particle. The particle is almost certainly the metal from the hole in the contact. The contacts are made from silver. The plastic cover of the relay fits very tightly, so it is unlikely that the particle came from the outside. This is a microscopic image of the contact that shows a hole in its surface. The hole is quite deep. I have never seen anything like this.

I bought a Klein Tools tracer to help me follow wires behind the dash and in the fuse boxes. Unfortunately, it was no help. The signal seems to couple into adjacent wires, and at the same time the signal weakens in the correct wire. Within one foot you can't tell which wire the signal is on. The tracer may work well in AC wiring in a house where the wires are spaced apart, but it does not work when all the wires are in a bundle.

I have been going through the same thing with my (new to me) 2002 Monaco Signature Series. The solenoid in blue feeds the "domestic" fuse block in my DC panel next to the driver side front wheel. The solenoid in green feeds the low current DC panel on the left (driver) side of the engine. The two solenoids, blue and green, are connected together and are operated by the battery cutoff switch on the dashboard. When the house batteries are connected, as in normal use, both solenoids get hot. I decided that I would figure out what went wrong. The solenoid looks OK when removed. I drilled out the rivets and opened it up. There is some black dust inside. Here is the problem, the contacts are oxidized. This is likely from the excessive heat that the solenoid is subjected to continuously. The coil looks OK, it is clearly not burned up. The varnish on the windings stood up to the heat with no problems. However, the insulating material has crumbled and turned to dust. Perhaps the dust got on the contacts and prevented a good connection. Or, perhaps the dust bound up the sliding mechanism and prevented the solenoid from closing properly. I hope that the new solenoid that I installed is made with better material. A word of warning about working with high current DC. Always turn off both DC disconnect switched before working in there. Some of these connections are not fused, so you are working without any protection. A short circuit can result in an explosion of molten metal blasting into your face. With 12 volts you won't get electrocuted, but you can still get badly injured.