12 volt power to rearview monitor...

Ramzfan · 09-13-2012, 11:39 PM

I have a little problem on my 06 Meridian 36G...my rearview monitor quit on me a while back, so I took it to a repair shop to get it fixed. The man tested it while I was there and said it had a blown transformer. He ordered a new one and installed it and everything worked fine, while it was on his workbench. When he installed it in the coach, it didn't work.
He tested the power feeds and said that I have no 12v power getting to the monitor. I am guessing that there is probably a fuse somewhere that got blown when the transformer went out. The trouble is, I can't find it. I checked all the fuses in the panel under the hood and none were showing bad. I think it must be an inline fuse but where do I look? Does anyone have a wiring schematic that would show if there is one and where it is? I'd appreciate any help I can get.

nightriderrv · 09-14-2012, 06:02 AM

I think there is can you trace the power wire on the monitor back

Ramzfan · 09-14-2012, 08:47 AM

Quote:

Originally Posted by nightriderrv

I think there is can you trace the power wire on the monitor back

I can only trace it so far, then it goes into a huge bundle of wires.

nightriderrv · 09-14-2012, 08:52 AM

Then it might be in one of the panels most likely in the chassie fuses use a light tester it's faster than pulling fuses out if you get one that don't light up just pull it to see if it's bad

cbeierl · 09-14-2012, 05:21 PM

Here's the Backup Monitor Installation diagram for your coach. It shows power connecting to WIRE ASM-IP,MAIN behind the monitor. On the 2nd page of the Automotive Wiring Diagram pdf for your coach you'll find a connection to the monitor in the bottom center. You should be able to trace the leads from that diagram (note that one large sheet is split across several pages of the pdf, so you'll need to move from the left edge of a page to the right edge of the previous page, etc.).

Note also that all of the Winnebago wiring should be labeled every few inches. You can refer to this Wiring Identification Guide to find out what any given wire is for.

Ramzfan · 09-14-2012, 05:53 PM

Thanks Chris...that should help! If I still can't trace it down, I figure I can bypass the regular 12v wire and just connect a hot one from the ignition.

Ramzfan · 09-15-2012, 08:23 PM

To Chris Beieri: Chris, I checked my wiring and I have three wires that go into the power outlet at the rear of the monitor...One is red and is fused, it connects to a yellow 14 ga wire marked JJZ. One is white and it connects to a white ground wire. the third one is blue and it connects to a yellow 16 ga wire marked TR3. This wire goes to the trip computer, according to the wiring diagram.
The red one has 12v power. The blue one does not. The man who repaired my monitor said that both of them needed to be hot. I am not sure. The last thing I want to do is connect a hot wire to a wire that is not supposed to be hot. Got any ideas?

cbeierl · 09-15-2012, 10:46 PM

Quote:

Originally Posted by stvscharfe

To Chris Beieri: Chris, I checked my wiring and I have three wires that go into the power outlet at the rear of the monitor...One is red and is fused, it connects to a yellow 14 ga wire marked JJZ. One is white and it connects to a white ground wire. the third one is blue and it connects to a yellow 16 ga wire marked TR3. This wire goes to the trip computer, according to the wiring diagram.
The red one has 12v power. The blue one does not. The man who repaired my monitor said that both of them needed to be hot. I am not sure. The last thing I want to do is connect a hot wire to a wire that is not supposed to be hot. Got any ideas?

According to the Wiring Identification Guide the yellow JJZ wire connects to the general purpose run/accessory feed #1--that should be the power for the monitor. You indicated that you have power here--that is good.

The white NG wire is a ground.

The third yellow wire should be labeled TR (not TR3) and is on pin 3 of the plug. That connects to the backup light circuit. You should see 12V on this lead when you are in reverse. Presumably the monitor owners manual would describe how this signal is used-perhaps to turn on the monitor automatically for backing, or to automatically switch from a side camera view to the rear view.

Ramzfan · 09-15-2012, 11:15 PM

Thanks Chris, I will try that tomorrow. The way I see it, if I put the coach in Reverse with the engine running, the wire labled TR should be hot w/ 12v...? If not, that is probably my problem. If it is hot and the monitor still doesn't work, I'm taking it back to the repairman. I'll keep you posted.

cbeierl · 09-16-2012, 12:32 AM

I would expect the monitor to work whether or not the 'backup' line is hot.

On my Sony Color Monitor (Model VCB-MHD1) the monitor will automatically turn on (even if the power switch is 'off') and display the rear view camera image when the ignition is on and reverse is selected.

Btw, if your monitor supports multiple inputs, make sure that you have the correct one selected for your rear view camera.

Ramzfan · 09-22-2012, 04:24 PM

Hi Chris,
I have the monitor working. The problem now is that it only works when the coach is in reverse gear. Both of the side cameras as well as the rear camera are working. It does not work though, when the coach is in Drive gear. The only thing I can figure is that maybe a wire from the gear selector came loose...? I am at a loss...any suggestions?

cbeierl · 09-22-2012, 04:41 PM

I think there must be something wrong in the monitor--I would take it back to the repairman and have them fix it correctly. With the monitor switched on (and power to the JJZ wire) the monitor should be operational. If you put the transmission into reverse (so the the TR wire has power) then it should be operational even when switched 'off'. In either case it needs power on JJZ.

Ramzfan · 09-22-2012, 05:36 PM

Thanks again Chris...you make it very easy to understand. I will take it back to the repairman Mon or Tuesday and explain how it is supposed to work. Now that I understand the functions of the different wires, I'm sure that he will also. I'll keep you updated.

Ramzfan · 09-29-2012, 12:09 PM

I removed the monitor on Tuesday and took it back to the electronics repair shop. I explained exactly how it was supposed to work to him and gave him a written explanation of what each colored wire's function was. He said he would take it apart again and see what he could find. He seemed to be happy to understand exactly how each wire was supposed to work. I will keep you updated on my progress. Thanks again.

Ramzfan · 11-04-2012, 10:07 PM

Well, Chris, I finally got the monitor back from the repair shop and when I installed it today, here is what it did:
With the monitor on and engine running, there is no power to the screen even though the JJZ wire shows power. When I put the coach into Reverse and the TR wire gets power, the monitor comes on and the side cameras both work.
The way I see it, I can take it back to the repair shop again or I can bypass the backup light circuit and just keep both wires hot all the time.
What do you think...?

cbeierl · 11-04-2012, 11:16 PM

It sounds to me like there may be a problem with the 'Power' switch and/or it connecting wires. The electronics obviously work. Did the repair shop feel that they actually fixed something? I would be inclined to investigate that switch--perhaps jumpering around it to see if that makes things work.

In my case I have the rear monitor on all the time when the coach is running, so it wouldn't be a problem for me to apply 12V to that monitor input to force it on. If you do that you should either disconnect the lead from the reverse circuit or put a diode in the circuit so that you don't back-feed power to the reverse circuit--I have no idea whether doing so would cause a problem somewhere else, and I think it's best to avoid the issue.

Ramzfan · 11-07-2012, 10:38 AM

I don't think that there's anything wrong with the power switch because it works when the monitor is working...I have turned the monitor on and off when I'm in the "Reverse" mode and it seems to be all OK. When I'm in "Drive" mode though, there is nothing, even though I've checked the power and it's hot.
What I thought about doing with the reverse wire is to cut it and cap it off, tap into the main power wire and attach that to the wire that used to be the reverse wire. I'm like you...I leave it on all of the time anyway and I can always shut it off if I want to with the power switch.

cbeierl · 11-07-2012, 03:29 PM

There's still something fishy about the power switch or its wiring. The switch isn't really an ON/OFF switch but an ON/STANDBY switch. With the reverse signal active it shouldn't matter what position the switch is in--you should get video. Without the reverse signal you should get video if the switch is in the ON position.

DAN L · 11-08-2012, 05:09 AM

the 12v power to my back up camera system is on the same circuit as the coach heater blower switch.

Ramzfan · 11-08-2012, 09:43 AM

Chris, I notice that when I put the coach in Reverse, I suddenly get power to the monitor. All of the little buttons light up and everything, including the side cameras are working. If I press the power switch, it shuts everything off, including the lights on the face of the monitor.