Wiring the 42RLE overdrive for off by default


Brianj5600

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We had to find that stupid reverse light wire for a back up camera system. If you put it into reverse, the system would default to the front facing camera and without that momentary trigger from the reverse lights when you shifted from park to reverse, it didn't work right. All due to the stereo installer not naming the camera inputs correctly.

Have you taken Chris' Jeep for a test ride yet? I'm curious if you feel the need to turn OD off with the FRP tune.
 

Chris

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Have you taken Chris' Jeep for a test ride yet? I'm curious if you feel the need to turn OD off with the FRP tune.
There is no tune anymore, it has a new ECM for the automatic conversion. I’ll have to get a new tune from them for the automatic.
 
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MountaineerTom

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To make the overdrive switch still function but turn off automatically as you shift into gear (which is about when I think about it.)

Get a common 4 or 5 pin lighting relay, I used Dorman part #88069 but a 4 pin works if it operates the same..there are different kinds.

1. Find the green/white back up wire at the drivers side rocker panel...run that to pin 86

2. Tap the overdrive swiitch green wire to pin 30

3. Tap the overdrive switch blue wire to 87 (this may be orange on some models)

4 . Run 85 to ground

87a is not used.

The reverse light switch wire pulses the overdrive switch when you pass reverse to drive , just like pushing the button does.

It stays off until you turn off the ignition or manually overide it for higher speed driving. In effect, the green/white reverse wire power now does for you what your finger did, all else remains the same.

Thanks to @Jamison C for advising me, tune in tomorrow as we explain how the pyramids were built.

Hope you auto guys like this as much as I do.

Andy G

Thanks for doing this. I may have to try it. It’s cool that it seems so easy because I’m not great with electrical stuff; no confidence.

Where did you mount your relay?

Does the orange indicator light work the same as it did before the mod?
 

Maso

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Here is a couple of pics of the wires and connector of the OD switch in a 2006 TJ, Export. In case anyone's interested. I haven't done the mod yet, just wanted to see what it looks like for now.

1.jpg


2.jpg
 
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AndyG

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Thanks for doing this. I may have to try it. It’s cool that it seems so easy because I’m not great with electrical stuff; no confidence.

Where did you mount your relay?

Does the orange indicator light work the same as it did before the mod?
Sorry, just saw this..relay is just above the switches , there is room but behind the kick panel is optimal...the light works for sure ......it turns on as you shift to drive and stays on until you hit the switch or kill the engine. Basically this mod reversed the default setting.
 
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MountaineerTom

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Sorry, just saw this..relay is just above the switches , there is room but behind the kick panel is optimal...the light works for sure ......it turns on as you shift to drive and stays on until you hit the switch or kill the engine. Basically this mod reversed the default setting.
Awesome. Thanks.
 
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AndyG

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Awesome. Thanks.
Pm and I will give you my cell number if you need it ....I am no electrical whiz at all.

This mod basically works as if the Jeep came this way - it seems factory. No glitches or anything to remember. The switch is a momentary. When you hit it you are sending a pulse to the transmission module or whatever that turns off the overdrive. All this is doing is over riding the switch with a pulse sent from the green and white back up wire you briefly activate as you pull the shifter back. For whatever beautiful reason it won’t do anything more to the overdrive if you shift to park and back to reverse or drive ....so it does just what you want ...the overdrive stays off as if the mod didn’t exist. The light works and the switch still works.

The net result is you feel like you have a 3 speed with optional overdrive, not mandatory.
 
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MountaineerTom

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Pm and I will give you my cell number if you need it ....I am no electrical whiz at all.

This mod basically works as if the Jeep came this way - it seems factory. No glitches or anything to remember. The switch is a momentary. When you hit it you are sending a pulse to the transmission module or whatever that turns off the overdrive. All this is doing is over riding the switch with a pulse sent from the green and white back up wire you briefly activate as you pull the shifter back. For whatever beautiful reason it won’t do anything more to the overdrive if you shift to park and back to reverse or drive ....so it does just what you want ...the overdrive stays off as if the mod didn’t exist.

The net result is you feel like you have a 3 speed with optional overdrive, not mandatory.

Thats great! Sounds easy enough.
 
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AndyG

AndyG

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I really want to hear success stories. Be sure you get the right trigger wire and ground the relay good. The switch wire to the starter relay is used in the Mustang world I believe ...but the reverse wire is excellent because you can’t go to drive without passing reverse. I declare it all sounds too good to be true, but it’s a clean mod with no drawbacks if you prefer overdrive off . I still watch it turn on the light when I put my TJ in gear and grin. You aren’t having to fix a design problem every time you drive it.
 
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