Wiring for Backup Camera

[RaisingWheels1]

Howdy!

I'm a newbie and lurker, but I'm here for a completely different reason than most of you, as we purchased a used school bus to be our family vehicle, not to transform into an RV. My apologies for the lengthy thread, I just know sometimes it's easier to start with our background on WHY we need, and are using the bus.

Let me explain. My wife and I have 2 amazing sons that have an extremely rare mitochondrial condition that causes a global overall delay and requires them to use manual wheelchairs for their mobility. If anyone has ever watched the HGTV show "Fixer Upper", our family was blessed beyond measure when Chip and Jo and Tim Tebow helped our family with a fully accessible home for our boys that originally aired in January 2018!

Our family is very active and after the blessing from "Fixer Upper", we felt it was our duty to pay it forward and started the Raising Wheels Foundation to help other families in our position. With this added responsibility, our family is even more active than before and travel all over the state of Texas for specialist appointments, summer camps and Foundation events. Well, we were, before the Coronavirus came along anyway.....

We were quickly outgrowing our minivans and I was originally researching shuttle buses. Long story short, a friend heard about our story to obtain a larger vehicle for the boys and created a GoFundMe to help us raise funds. During that time a friend suggested a used school bus and our local school district was auctioning 6 identical buses previously used as SPED buses with 2 A/Cs, and of course, wheelchair lifts. While not the engine I was hoping for after MUCH research on this site, our family made the decision to bid on the bus I liked best and were able to win it!

The bus is a 2007 IC 200 CE 30' short bus with a VT365 engine and Allison transmission. It has a 5.29 rear end and will cruise pretty easily at 65 with the cruise control set, running around 2400 RPM. Due to research on this site, I immediately purchased a ScanGauge D to monitor the EOT, which ranges from 200 to 220 degrees on the short trips (within 30 miles) I've made to get a feel for how it drives. Fuel mileage is pretty terrible according to the ScanGauge, only 1.4 MPG average. That doesn't seem to jive with instant MPG on the dash. Also randomly has puffs of black smoke and while doing research before purchasing, found out from Navistar that the injectors were replaced early on under warranty but unsure of anything done by the school district before retiring it. We knew repairs would need to be made when we purchased it and are planning to get them done when things get back to "normal."

I understand many of you have a severe distaste for this engine and I respect that, but please understand we do not have the luxury of waiting for the perfect bus to come along with our situation. So in our case, we feel the perfect bus DID come along, we're staying positive. I fully intend to get the engine bulletproofed, but I'm digressing from my question.

I purchased a backup camera system that allows me to connect 2 cameras. I installed one on the back of the bus as a primary backup camera. The second, I installed in the center of where the wheelchair lift will come down, so as I pull up to sidewalks, etc., I can see exactly where I need to park to lower the lift and load and unload the boys safely.

When I initially had this idea, I was thinking there was a light I could tap into under the wheelchair lift door. Unfortunately I was wrong, the lights are actually built into the lift itself, so that's out. After getting under the tail of the bus, I found 6 wires in a loom that I assume are the rear lights. Tonight I attempted to use the wire taps provided with the camera, but ran into 2 issues.

1.) There are 2 red wires, 2 white wires and 2 gray wires.
2.) After tapping into 1 red wire and 1 gray wire, I had no power to the camera. (The black tape is what I put over the failed attempts.)

For those of you more experienced with bus wiring, did I try to tap into the wrong wires? What is the gray wire? I assumed it was essentially the negative, but I couldn't find anything confirmative on any sites to tell me what it was. I'm also not sure I was able to get a good tap with what the manufacturer provided, but I wanted to ask on this forum first before trying again and potentially shorting something out.

ANY help at this point is greatly appreciated!!!!!

[CHEESE_WAGON]

I can't say for sure which wire is which without a schematic. What I can tell you is that in most DC circuits, lighter colored wires tend to be 12V+, darker colored wires tend to be ground. Occasionally grounds will be signified by a dark stripe on the insulation, and 12V+ can sometimes be indicated by a light-colored stripe on the insulation in cases where similar colored wires are used for the same circuit.

What I would suggest for triggering your side camera is this. Most vehicles have a switched 12V coming off of your turn signal switch for each side, into the flasher. I would wire up a 12V relay for each camera.




The one for the camera intended for the handicap ramp, I would tap the relay's trigger wire into the right-side 12V output from the turn signal switch, or maybe for the 12V output for the hazard flasher relay, as I presume you would be using either the right turn signal or the flashers to indicate you are stopping at a curb.

The relay for the actual backup camera, can be triggered off of the 12V output from the reverse light switch / relay. Chances are you can find both circuits at the front of the bus to power the monitor(s), which may save some hassle and wire. You might consider re-purposing the wiring circuits run for the amber and reds up top for this, if you won't be using the amber/ / reds anyway.

It also occurs to me the camera on the handicap ramp could serve as a nifty little blind-spot camera, in which case, you don't necessarily need it switched on-demand, perhaps a switched 12V from the ignition switch could work for this one.

You can use a test light with the appropriate circuits receiving power to check to see which wire is powered, and most any metal surface in the bus body or nearby ground wire will do for grounding.

Hope that helps.

[RaisingWheels1]

Thanks Cheese_Wagon for the reply! One thing I forgot to mention is that the system is a wireless system, so I don't have much wire to play with. Today I tried to see how far I could go, but nowhere near where the wiring and fuses are. Does that make a difference in your advice?

I did find after I posted yesterday that the gray wire is apparently part of the No Child Left Behind safety system, so doubt that was a negative wire.

Today I tried a different route. Because the wires provided for the camera are only a few strands, I tied those to an inline fuse for the positive and used a bigger tap to try and tap the red wire. I tied the negative to a larger gauge wire and found a screw to ground everything. Unfortunately, I never could get the camera to power on. I'm not going to pretend I know much about automotive wiring, so I'm completely at a loss. Seems like every time I get something that should be a "plug and play", I spend hours trying to make it work!

[CHEESE_WAGON]

Thus proving there really is no such thing as Plug and Play.

[magnakansas]

run two wires from the drivers control center to the cameras one 12v+ and one 12v- and put the fuse as close to power source as you can.... I would try to convince you to have cameras on all the time.

william

[RaisingWheels1]

Thanks William! Yes, that's actually what I want, to have both cameras on at all times. The backup camera up high is on because I was able to tap into the clearance light. It's just the camera under the wheelchair lift I'm having issues with. I was hoping to avoid running wires all the way under the bus, but it looks like they may be the only viable option since I can't make a good connection with the camera wires provided.

[Native]

Originally Posted by CHEESE_WAGON

Thus proving there really is no such thing as Plug and Play.

To me, Plug and Play means ... plug it in and keep playing with it until it works.


To the OP ... If you are happy with powering the backup camera via the clearance lights then why not run a short wire from a side clearance light to the side camera? You can obtain the ground near the camera. One more tip ... if you do not have a multi-meter get one. Harbor Freight has them for close to nothing.

[Phatman]

I am assuming there are no device markings on the wire? Sometimes there are markings every 12 inches or so.

[RaisingWheels1]

Native - Unfortunately the only clearance lights I have on the side are the top lights on the rear of the bus or the one in the top corner. Everything is sealed up super tight with all wires going into the bus in the loom. Otherwise I'd have no issue tapping into a side light. And thank you, I do have a multi-meter. For some reason I was unable to even get a reading! I had read somewhere that LEDs won't have enough of a charge to power a backup camera, have you ever heard that? I thought maybe that's why I wasn't getting a reading, but seems to me SOMETHING would have to being flowing through the wires to even get power to the LEDs..... But, all of the lights are LEDs other than the headlights.

Phatman - No, I didn't notice any markings, but all the wires in the loom were caked with dirt and mud. I rubbed off some of it and the pic was taken in the dark using the flash. When I get a chance I'll get back under there and clean them off better to see if there are any markings.

Thank you both for the feedback, I'm determined to make this work!

[Native]

Originally Posted by RaisingWheels1

Native - Unfortunately the only clearance lights I have on the side are the top lights on the rear of the bus or the one in the top corner. Everything is sealed up super tight with all wires going into the bus in the loom. Otherwise I'd have no issue tapping into a side light. And thank you, I do have a multi-meter. For some reason I was unable to even get a reading! I had read somewhere that LEDs won't have enough of a charge to power a backup camera, have you ever heard that? I thought maybe that's why I wasn't getting a reading, but seems to me SOMETHING would have to being flowing through the wires to even get power to the LEDs..... But, all of the lights are LEDs other than the headlights.

Phatman - No, I didn't notice any markings, but all the wires in the loom were caked with dirt and mud. I rubbed off some of it and the pic was taken in the dark using the flash. When I get a chance I'll get back under there and clean them off better to see if there are any markings.

Thank you both for the feedback, I'm determined to make this work!

The LED lights may draw little current, but they have to use the voltage supplied ... 12 volts.


Hey ... we are in Hurst (next to Fort Worth) ... where abouts are y'all in Texas?

[RaisingWheels1]

Native, we’re in Waco, not too far from you. Lawson, my youngest, has a wish through Make-A-Wish for a Magic School Bus from MAW North Texas, so RW1 will probably be up your way one day. They are going to trick it out with lights, TVs and stuff to help on these long rides to Houston for their specialists. So honestly, I probably shouldn’t even be messing with the camera, it’s a pride thing at this point. ��

[Native]

Well, if we are ever driving through your neck, we'll be sure to stop and lend a hand or just chat. [That's my wife and I ... the "we".]

[RaisingWheels1]

Thanks Native, I'm always willing to learn a thing or two and make new friends!

As for the camera situation, it's actually not me this time. I decided to just run wire from the batteries to see if I could get the camera to turn on and nothing happened. So I hooked it up the way they advise you to test the camera once you receive it and it's dead. This is the second camera, the original crapped out on me as well and this is the replacement. I've contacted the company to see what they can do, wondering what the failure rate is on these cameras?!?!

[CHEESE_WAGON]

Reverse polarity (12V+ to the ground wire and vice versa) will do that.

[jmiraglia]

If your bus is like ours, there is no negative wire running back to a central fuse panel. Our bus' negative is the bus itself. You can test this with a multimeter (or LED) by connecting positive terminal of multimeter to one of your wires, and negative terminal to an exposed metal surface of the bus.

[RaisingWheels1]

Thanks jmiraglia, that totally makes sense! I've been curious about that because when I was looking in our second panel with many of the wiring connections, there are no negative wires, only positives. I thought that was rather odd, but was going to ask our dealer when I take it in for an oil change.

[BusWanderer83]

You really need a voltmeter. Put the black test lead on the metal frame, use a wire brush to clean it for good contact. Then start sticking the red one on the copper part of the wires. Do not leave electrical tape on the wires if they come anywhere near metal, you'll be best served cutting them and reconnecting the wires with heat shrink butt connectors with some gel to keep water out. You will start blowing fuses as soon as the electrical tape falls off. You should be able to avoid running wires if you find voltage that's already there..

[RaisingWheels1]

Thanks BusWanderer83, I do have one. Unfortunately I wasn't getting a reading before when trying to use it, but I was trying to figure out which other wire was a negative and I fully admit it was probably user error. I'll take your advice on using the bus as the negative to make sure the red wire is my positive. I did speak to our local bus dealer and he said the red wire SHOULD be the positive, but certainly not always and as many of you have mentioned, I'll just need to test the wires with a voltmeter to find which one has the juice.

Thanks again for the replies, the camera manufacturer can't figure out why the cameras are dying either and are sending me a new system that should be here this weekend. Supposedly it's their updated system, so hopefully I'll have better luck this time around.

[BusWanderer83]

There is an old saying in the cabling business that goes "the only standard is there is no standard". This is especially true in one-step-above custom items like buses and when you throw in previous owners... I think your best bet is to run some new wires back to the camera. See if you can find some outdoor-rated cable in the 18-20 awg range at your local Graybar and nonmetallic p-clips. Very short self-drilling screws should be relatively easy to install. I wish I was closer to Texas so I could give you a hand

[RaisingWheels1]

Thanks again BusWanderer83. If you were closer I'd certainly take you up on the offer!

I have to admit though, I've learned more than I ever thought I'd even care to know about buses in the last month and a half. I'm picking up on some of the terminology and between my experience spec'ing and purchasing vehicles in my prior life, and researching stuff on the web, I feel more confident in owning and using the bus as our family vehicle. Obviously I'm not ready to jump into the deep end and replace an engine, but at least I have more knowledge about some of the simpler things. Skoolie has been a gold mine of information and I appreciate everyone's suggestions and ideas!