reverse light activation

Printed From: the12volt.com
Forum Name: Lights, Neon, LEDs, HIDs
Forum Discription: Under Car Lighting, Strobe Lights, Fog Lights, Headlights, HIDs, DRL, Tail Lights, Brake Lights, Dashboard Lights, WigWag, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=113261
Printed Date: May 07, 2025 at 6:12 AM

Topic: reverse light activation

Posted By: dopark1
Subject: reverse light activation
Date Posted: April 18, 2009 at 11:22 PM

I am trying to use the reverse light indicator swtich on my 2007 grizzly 700 atv, to activate the 55w light I mounted on the back of it. When the switch is grounded the R light is off. The switch bolts to the transmission case and there is only one wire, it goes to the ecu. I have a 40 amp, SPST relay. Will this do the job? Need a specific diagram for this if possible.

Replies:

Posted By: i am an idiot
Date Posted: April 19, 2009 at 12:31 AM

The 40 amp relay should be adequate for your light. Can you get a voltage reading on the wire when the R light is on on your dash?

Posted By: dopark1
Date Posted: April 19, 2009 at 12:56 AM

I will get that voltage reading first thing when get up tomorrow.

Posted By: dopark1
Date Posted: April 19, 2009 at 1:02 PM

When the gear is in reverse, the volts on the switch wire reads 12 volts. Wiring the relay in the basic setup does not work, when the ground is attached to the relay the reverse light does not work.

Posted By: i am an idiot
Date Posted: April 19, 2009 at 2:31 PM

Can you get to the actual bulb on the dash? Read the voltage across the bulb when it is lit. If that is not easy to do and you feel comfortable doing a little soldering on a transistor that is available from Radio Shack I can get it to work for you.

posted_image

Relay wiring as follows. As stated on diagram right leg of transistor connects to 86 of the relay. 85 of relay needs to be grounded. 30 connects to 12 volt source fused at 5 amps. Maybe 10 amps, do not remember about your lamps. Terminal 87 connects to the hot wire of the lamp. Ground the other wire of lamp if there is one. If no other wire, it grounds through the mounting bracket.

Posted By: dopark1
Date Posted: April 19, 2009 at 2:58 PM

I can't get to the reverse indicator bulb. But your transistor idea is very interesting! I will be trying that tomorrow. Thanks. I will keep you posted

Posted By: dopark1
Date Posted: April 20, 2009 at 11:24 PM

(I am An idiot?) Your idea worked perfect, I didn't think it would but thank you for proving me wrong. Thank you very much!

Posted By: i am an idiot
Date Posted: April 21, 2009 at 5:26 AM

You mean no fire, and not even a little bit of smoke?

Posted By: dopark1
Date Posted: April 21, 2009 at 3:25 PM

Only when I realized the new reverse switch I bought from yamaha was defective! Fire and smoke coming from my nose!