First, I have read everything already posted on how to wire a backup LED using the Reverse Switch to make/break the ground to have the LED turn ON when the transmission is shifted into Reverse. I understand the recommended approach. I also have the factory service manual and can read the wiring diagrams. I have done far more complex automotive wiring jobs on other machines. This seems straight-forward...but it’s not. I ran a temporary ground wire to the Reverse Switch connector at the bottom rear of the engine making sure that wire is NOT accidentally grounded to the engine case. It is not. With the transmission in Neutral (or Drive), there is no continuity between that wire and ground. This is good. To put the machine in Reverse, with the engine running and the trans in Neutral, you pull the small ”P/R lever” on top of the rear brake lever rearward and pull the rear brake lever, then depress the transmission downshift switch. At that point the trans goes into Reverse, the digital display shows “R” and I get continuity on the temporary ground wire and my LED turns ON. All this is good. However, as soon as I release the brake lever the LED goes OFF even though the machine is still in Reverse. My volt/ohm meter shows I lost continuity to ground on the temporary wire. As soon as I pull the “P/R“ and brake levers, I regain the ground. This makes no sense to me as the transmission is still in Reverse. My intention is to have the LED stay on as long as the transmission is in Reverse without needing to have the brake partially engaged. What am I doing wrong or is the wiring or the Reverse Switch on the 2019’s different than what is shown in the 2014-2019 Service Manual? Everything else on the machine works as intended. Any constructive suggestions will be greatly appreciated!
2019 TRX420FA6 backup light trouble
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So you only loose continuity when the brake lever is released? Is the a switch on the bars at the lever?
An alternative suggestion of course would be to just wire the LED to a switch. I do see the practicality of having it work when reverse is engaged though.
An alternative suggestion of course would be to just wire the LED to a switch. I do see the practicality of having it work when reverse is engaged though.
SamUK- the switch I am referring to is called the Reverse Switch and is located at the bottom rear of the engine, directly to the left of where the cable that is activated when the left handgrip Reverse Lever is pulled attaches to the rear of the engine. According to all of the previous posts I have read, this switch is activated (grounded) internally by the cable when the Reverse lever is pulled. That grounding completes the circuit and permits the Reverse light (or the ‘R) in the digital display to come on. I read about this in numerous posts dating back to the 2008-2012 timeframe. The switch has one wire attached to it. This is shown on the wiring diagram of the service manual. The switch goes to ‘ground’. The previous posts said to use that wire as the ‘ground’ for the LED Light. The other side of the LED is hooked direct to the battery. When I hook the LED up that way, the LED does not come on until I shift the trans into Reverse. However the light goes out as soon as I release the left handgrip Brake/Reverse lever even though the trans is still in reverse This is NOT what I expected based on all of the previous write ups. This method does not require a relay since I am getting power direct from the battery, and only using the Reverse Switch wire as the ground. This method also has the advantage of being completely passive....the driver does not have to do anything to turn the light on other than to switch the trans into Reverse...just like a car or truck. Nothing to turn on or off, and only works when the machine is running, so there is no chance of walking away with the light on possibly draining the battery.
I know how to hook it up with a relay, and for the time being I have tapped the Brake Light Switch (left handgrip) for the ‘trigger’ for a relay. The light comes on as soon as either brake lever or the foot pedal is slightly engaged. The reality is this will work OK as I don’t back-up long distances and my hand is usually on the left brake lever anyway. However, the LED comes on every time the brakes are applied!
I bet I could figure it out by talking the instrument panel apart and trace out what actually happens when the ‘R’ light comes on, but there is practically no information in the service manual on what makes the display work. Since this is a brand new machine, I really don’t want to poke around without basic information!
Any and all information on how to do this using the Reverse Switch will be greatly appreciated.
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Yes, it goes out as soon as you release the lever because the circuit is broken once lever is released. I'm pretty sure electronic trickery takes over once the lever is released, meaning the CDI (or something) keeps the R light illuminated on the dash.
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I have a 2019 honda rancher and the simplest way to add a back up light is to use the grey wire that that runs from top center (by the fuel tank)it goes down the right side of the quad I tapped into that for the ground side I used a diode to prevent back flow and for the positive side I tapped into the acc/ignition wire so it only works with the key on. I soldered the wires and put heat shrink tubing on them and sealed it with liquid tape. It works great no problems
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