Tech Tips

Backup Camera GPS Input

Most if not all of us that have a backup camera use it to keep an eye on the towed vehicle while driving. But, I thought it would be neat if I could route my laptop GPS screen to the backup camera via the AUX 2 input. I have a Voyager backup camera by ASA and sent them an email to see if this could be done. The answer was yes, if the output was a NTSC signal (TV). They had an adapter for $10.99. My laptop has an S Video out so I searched the Internet and found a 12' S Video to RCA cable. Put the 2 together and you have complete cable. Well, you actually need a 2:1 audio cable as the backup camera is Mono and the laptop audio is stereo.

Note - ASA Electronics  is part of Jensen. The cable can be found at  Jensen RV Direct and click on Observation.

Patch Cables

Now all I needed to do was hook the cables to the backup camera and the laptop.

Back Camera


Last but not least is to configure the laptop to show the GPS screen. I have Windows XP with an ATI Radeon video chipset. XP supports dual monitors so I tried that first and was able to get the desktop to display on the backup camera. But, that does not display the GPS application. If you use the ATI interface you "Clone" the desktop per si. This allows the application to be viewed. The only down side is that you must set this up each time you use the system.

As far as the audio goes, you can plug the audio cable into the speaker port and get the audio from the back cameras speaker. It’s not really usable when you consider the background noise when driving. Also, it shuts of the laptop speakers.

Lastly the display only supports 640x480 and it is not the sharpest resolution.

GPS Display

The bottom line is.... It does what I want it to. I can see the map and next turn info while my wife watches the main screen on the laptop.

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Most, if not all of us RVer's check the tire pressures before each trip and some of us check the tire temps when we stop for fuel or at a rest stop. But, once you get on the road you never know what the pressure is or the temperature of the tires while you are on the road. So, what is the answer? Add a TPMS (Tire Pressure Monitoring System). There are any number of systems out there such as Doran Pressure Pro, Hawkshead, Hopkins, TST (Truck Systems Technologies) and maybe a few others. I settled on the TST TPMS system as it is small, easy to install, easy to configure and priced right.

What's In The Box

  • Owners Manual
  • Long Antenna
  • Power Cords
    • Cigarette Lighter Adapter
    • Direct Connect Adapter (+12 Volts & Ground)
  • Sensors
  • Accessory Bag
    • 2 Sensors Install Tools
    • 2 Vent Mounting Clips
    • Double Faced Tape
  • Display with short anntenna attached

Installing the sensors is a snap. TST provides a tool (anti theft device) to screw them to the valve stem. It is recommended that you have STEEL valve stems installed. Each sensor has a code attached to it so the display unit displays the correct info for each tire. I used a paint pen (Wal Mart Hobby/Crafts) to write the wheel position and id code just incase the paper one comes off or you have to remove the sensors. I labeled mine as follows:

  • DSF - xxxx (Drivers Side Front)
  • DSR - xxxx (Drivers Side Rear Inner Dual)
  • DSRO - xxxx (Drivers Side Rear Outer Dual)
  • PSF - xxxx (Passengers Side Front)
  • PSRI - xxxx (Passengers Side Rear Inner Dual)
  • PSRO - xxxx (Passengers Side Outer Dual)

Sensor Install

The display needs to be configured for each sensor and the you need to set the various parameters such a high/low tire pressure, temp F°/C°, high/low temp etc.

I found that my tire gauge was off by about 2 lbs. You will also lose a little air pressure installing/removing  the sensor.

Display Install

Extra Sensors

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J72 Autopark Brake Light Switch

I received the following Email fro a Beau Endres about how he fixed an Autopark Problem with help from Roger Hagg (oldusedbear).


When I was returning from the James Island Rally I noticed that I had a red light on the dash board that was not there when we started out. The light was “Auto Brake”. This was kind of weird as the motor home was operating normally. Once I got home the fun began trying to figure out what was wrong.

Reviewing the information I had gotten from Roger Haag previously it appeared the “light switch” was the culprit. I sent an e mail to Roger and his reply confirmed my guess.

The information below is what I sent to him.

This is for your information if questioned. I have since gotten a “rotten green switch” for stock. If one went the other might be close behind. CarQuest found it for me, but had to go to their local GM dealer for it and it was $62.00. A price for insurance.



Today the weather cleared and I got under the motor home and to my surprise I had an oil leak. The oil was from the brake unit and had me concerned that a hose or fitting might have broken. Once I got the cover plate down it showed only the light switch that was leaking, relief.

The switch was easy to access and removing the wire connector was easy, but it had held back quite a bit of oil.

I removed the old switch and held my finger over the opening, read the part number in the gray plastic area. Doubled checked your number and put it back in place, temporarily.

I called my local Car Quest and gave them the number off the switch, they crossed referenced to their system and had one in stock. For future reference the Car Quest part number is 53-47307, switch, interrupter. They told me used on power steering systems. List $42.00, net $ 25.00

I picked it up and got back under the unit.

I had to spay electrical cleaner on the wire connector to get the old oil out. Then removed the old switch and installed the new switch.
Note - That the thread is a machine thread with an “O” ring to seal against the “T” fitting.

I connected the wire and crawled out to test the installation. Everything worked as designed and I then went back under and installed the cover plate. I added a small amount of fluid to refill the reservoir.

All in all, the job went easier then I had first thought.

Please accept my sincere thanks for your help, with out your guidance I would have been fumbling around with this repair, you made me a very happy camper.

Beau Endres
depchief of IRV2

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R&R Cooling Fan

Most of us that have the dual cooling fans don't worry about them much. But, they do fail from time to time. Of course you can get a new one from the OEM or from Evans Tempcon, if you can find a dealer that has one in stock. But, you can also get a replacement from the local autoparts store.

I got the following from Jim Synder on how he repaired his failed fan.

The parts needed to fix/repair the fan assmembly are:

  • Imperial Automotive Products by Hayden
  • Part# 226112, 12" electric fan
  • Advance Auto parts
  • O'Reilly Auto Parts
  • Price: $61.09 + tax

Remove the fan blade and motor, due to the shroud mounts being a little different I used the original shroud and fan blade, though the blade is the same as the OEM part. Remove the electric plug and rewire to new fan motor (they are the same color blue/brown as OEM.) By using the stock shroud, just reinstall and plug in connector. It works perfect and is about $110.00 cheaper than quoted by dealers, plus they stock these units at their stores

Jim Snyder
Binghamton, NY

I had one fan not working at all and the other with a loud bearing that would probably have siezed very soon. I elected to replace both fans and would recommend that this should always be done even if only one has failed.

The electric aux. cooling fans in front of the radiator & A/C condenser can still be found (Pt. No. W8000087), but you will most probably have to pay in excess of $200 each. And, be advised that the fans turn clockwise, looking at them with the open bonnet.But,be advised that the workhorse pig-tail harness connector wires that mate with the workhorse fan motor wires are reversed with regard to wire color (Blue to Black and Black to Blue) for the fan to rotate clockwise.

Less costly replacement fans are available from auto parts stores like O'Reilly's and Amazon, but they are not exact replacements. The mounting points are spaced differently left to right and the height is 1/4" less than the original fan. This can be resolved by drilling four new mounting holes in the workhorse fan mountings and adding a 1/4" spacer above or below the fan.

  • Hayden
  • Part# 3680, 12" electric fan
  • O'Reilly Auto Parts
  • Price: $59.99 + tax
  • Depo
  • Part# 335-55038-200, 12" electric fan
  • Amazon
  • Price: $50.95 + tax

An easier solution is to remove the new fan motor from its frame and install it into the original workhorse fan frame. This worked best for me.

Now, you need to make the fan(s) rotate clockwise.

If you are using the Hayden fan(s), the wires are not provided with an installed connector. Cut off and utilize the connector on your bad workhorse fan(s) and connect the wires to get a clockwise rotation.

If you are using the DEPO fan(s), they are pre-wired for counterclockwise (CCW) rotation thru an installed connector. The easy fix is to cut and reverse the input wires of the workhorse pig-tail harness connector that feeds 12VDC to both fans.


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66mm to 73mm Brake Caliper Conversion

This brake caliper conversion was done by a friend of mine, Glenn Norman, the owner of OEM -Engineering. Glenn worked for GM at one time, also owned a couple auto repair shops and a body shop.

This write-up was orginally posted on and is posted here with permission from Glenn.

It is with great sadness that I am posting Glenn's passing. Glenn fought the good fight but could not beat the battle with cancer and passed away January 3 2015.

Here is a short tutorial on how to PERMANENTLY fix your OEM Re-Called Bosch 66mm Pin Slide Brakes on W-20 Thru W-22 Chassis:

CHANGE THEM TO THE 73mm Bosch Pin Slide Calipers and Pads.

The 73mm Calipers have NEVER had a recall, they are used on all Navistar (IHC) School bus Chassis over 26000 Lbs

GVWR with Hydralic brakes -1998 thru Current Production;
All Ford F650 Chassis 2004 thru Current Production;
All Navistar (IHC) 3700 thru 4700 Medium Duty Trucks;
GM Kodiac/TopKick 6500 chassis with Hydralic Brakes;
and many other chassis too numerous to list here, but you get the idea.

For those of you that have parked your rig because you are AFRAID to drive it - THIS IS YOUR FIX so you can get back on the road and FORGET ABOUT THE OEM RECALL FOREVER!!

What you need:

  • 4ea. ACDelco Part#18FR1514 Re-Man Calipers 73mm $110ea. (plus core exchange)
  • 4ea. Navistar (IHC) Part#2501845C91 Tie-Bar Kit w/Bolts $65 ea.
  • 2ea. ACDelco Part#17D786M 73mm Brake Pad Sets $60 ea.
    (The 73mm pads are thicker than the 66mm pads, but they are interchangeable if you want to use your old pads until they wear out.

Total parts cost (excluding Brake Fluid) = $820

I do my own labor, so if you have a shop do it, you will have to add the shop's labor cost to the $820.


  • You can also use Re-Man Calipers from Bendix Part# SL55850 and CarQuest Part#18-8058, as well as many other suppliers.
  • The 73mm Casting Number is 4153222 while the 66mm Casting Number is 4153269. These numbers are the same NO MATTER WHICH SUPPLIER you use. Also the 73mm calipers will have a large "73" cast into the back of the casting.

Read the "BOSCH Brakes - Pin SLIDE MANUAL" before you start this change. The file can be downlaoded by clicking on the above link. It contains all the necessary info for this change-out as well as all the bolt torque specifications and procedures. It is imperative that you read and understand it before doing the change-out. The maual page #46 gives all the different specifications for both the 66mm & 73mm Calipers - Please note the fluid capacity of the 73mm calipers is almost DOUBLE the 66mm capacity. Also note the exploded view of the calipers (fig.1, page 2) shows the installation of a SPLASH SHIELD, I did NOT have splash shields on my front brakes, but did have them on the rears. The instructions say the splash shields and ABS sensor brackets have to be installed on the opposite side of the anchor plate for the 73mm Calipers - I did NOT have to change my ABS brackets or the rear splash shields to accommodate the 73mm calipers. The Upper most Caliper Bolt on the rears was very close to my leaf springs when un-screwing it, but it did clear without having to remove the anchor plate or leaf spring U bolts to drop the axle for clearance. I had to use a 18mm boxed end wrench instead of a socket due to clearance, but it was not a problem. I have attached some photos of my rigs' front brake change-out and the rears are pretty much the same. My Chassis is a 2004 W-20 with 22.5 wheels built August 2003.

This change-out works with both the 19.5" and 22.5" wheels. Your ABS system is unaffected by the change-out and will operate as it always has.

Enjoy your new "FERRARI",,,errr I mean "OEM" brakes.

The 1st. photo is my original 66mm calipers, all the rest are the installation of the 73mm calipers and tie-bars.



73mm - 66mm Caliper Differences

66mm - 73mm Brake Pads

73mm Caliper Label

73mm Tie Bar

73mm Tie Bar Label

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Wiper Nozzle Repair

I had a wiper nozzle break while I was on the road. No problem just stop at the closest RV dealer and pick up a spare, right? Not going to happen if you have wipers made by Dyna (Made in Brazil). I thought about calling Newmar, but I figured they want to sell me the whole arm. So I started searching the internet a found Mill Supply that has lots of stepvan parts (IE - P32 parts). I downloaded the univwiper.pdf file and low and be hold I found the part. I ordered 3, 1 to fix my wipers and 2 spares.

As you see in the BEFORE photo the nozzle is bolted on to the arm and the little internal mounting tabs have broken. Very simple repair ONCE you get the parts. Just remove the small nut, remove the damaged part, install the new part and reinstall the nut.



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