FJ40 Flat Towing Wiring Help Needed!

1973Guppie · 08-12-07, 07:24 PM

So, I am wiring up my 73 FJ40 to flat tow behind my 2007 Tundra and am having some issues. I am using the stock 7 pin plug that comes on the back of the tundra and wiring it up to the FJ40. I am using a 6 pin connector on the fj40. I am using the diagram on the 7 pin tundra that shows the running lights (brown), ground (wht), LH stop/turn (Yel), RH stop/turn (Grn). So I took these wires and sent the brown to all the marker lights, tailights and license lights on the 40. I previously looked at the rear lights on my bumper and they have 3 wires, one ground, one for turn and one for running lights. I figured out which was which and then routed the wiring accordingly.

The problem: I tested the setup and when I turn the turn signals on the tundra on, I get BOTH of the rear tailamps blinking?? WTF? Weird thing is that when I test the fj40 on it's own, everything works as it should. So, if the fj40 wiring is fine what is making BOTH lights blink? I retraced my wiring and everything is wired up as it should, made sure green goes to green (etc) through the plugs. I just can't figure out WHY it would make both lights blink when each wire is going to only the appropriate bulb? Am I missing something or need to add something into the wiring?

I hate wiring, any help appreciated, this is taking way too long to get done.

Noah

camcruiser13 · 08-14-07, 11:42 AM

i am of absolutly no help but just wanted to say im glad its you and not me.

i have had my share of wtf's

what if you ised an adapter with 4 prings, simplify?

Living in the Past · 08-14-07, 05:03 PM

Do you still have stock wiring in your 73? Are you leaving all the wiring hookedup and just splicing into it? The brake/turn signals use the same bulb. In there normal state both right and left sides are connected. Try moving the turn signal switch to one way or the other with the ignition off. This will break the circuit between the two. If that works you will have to find a way to disconnect the turn signal switch.

John

KY854RUN · 08-16-07, 11:34 AM

Noah,

Why not use a set of magnetic towing lights like these with a 7 to 4 pin adapter?

Here is a link for them. http://www.southwestwheel.com/store/p-3145-va52000.aspx

08-12-07, 07:24 PM	#1
1973Guppie IH8MUD Lifer Join Date: Jan 2003 Location: San Diego, CA Posts: 2,205	FJ40 Flat Towing Wiring Help Needed! So, I am wiring up my 73 FJ40 to flat tow behind my 2007 Tundra and am having some issues. I am using the stock 7 pin plug that comes on the back of the tundra and wiring it up to the FJ40. I am using a 6 pin connector on the fj40. I am using the diagram on the 7 pin tundra that shows the running lights (brown), ground (wht), LH stop/turn (Yel), RH stop/turn (Grn). So I took these wires and sent the brown to all the marker lights, tailights and license lights on the 40. I previously looked at the rear lights on my bumper and they have 3 wires, one ground, one for turn and one for running lights. I figured out which was which and then routed the wiring accordingly. The problem: I tested the setup and when I turn the turn signals on the tundra on, I get BOTH of the rear tailamps blinking?? WTF? Weird thing is that when I test the fj40 on it's own, everything works as it should. So, if the fj40 wiring is fine what is making BOTH lights blink? I retraced my wiring and everything is wired up as it should, made sure green goes to green (etc) through the plugs. I just can't figure out WHY it would make both lights blink when each wire is going to only the appropriate bulb? Am I missing something or need to add something into the wiring? I hate wiring, any help appreciated, this is taking way too long to get done. Noah __________________ Front disc brakes: http://forum.ih8mud.com/showthread.p...+brake+dummies 1973 FJ40 - Finished! Vortec/NV4500/ARB's/SOA FJ40 ROTW: http://forum.ih8mud.com/showthread.p...uppie%27s+fj40 1970 FJ55 - Restoration Project in the works /2F/AC/PS FJ55 Restoration Thread: http://forum.ih8mud.com/40-55-series-tech/102079-guppies-fj55-build-thread.html

08-14-07, 11:42 AM	#2
camcruiser13 IH8MUD Lifer Join Date: Jun 2004 Location: in the garage after dark in UT Posts: 5,101	i am of absolutly no help but just wanted to say im glad its you and not me. i have had my share of wtf's what if you ised an adapter with 4 prings, simplify? __________________ cc ------------- 76' fj40 camcrusier13 build threads the following are links, just click, go on try it Traction Bar Sliders Ram Assist Bumper Poison Spider Style Shackle Reversal Half Doors if your doing it im sure ive done it, need help just ask.......

08-16-07, 11:34 AM	#4
KY854RUN IH8MUD Regular Join Date: Apr 2007 Location: Northern Arizona TLCA# 3200 Posts: 343	Noah, Why not use a set of magnetic towing lights like these with a 7 to 4 pin adapter? Here is a link for them. http://www.southwestwheel.com/store/p-3145-va52000.aspx __________________ Kevin `85 4Runner - work in progress M416 Trailer - ukn year, rebuilt July 2007, build thread `68 FJ40 - planning stages of a build Green Country Cruisers - member Wish List - to long to post

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08-14-07, 05:03 PM	#3
Living in the Past IH8MUD Addict Join Date: Apr 2005 Location: Phoenix,AZ but it's a dry heat Posts: 1,475	Do you still have stock wiring in your 73? Are you leaving all the wiring hookedup and just splicing into it? The brake/turn signals use the same bulb. In there normal state both right and left sides are connected. Try moving the turn signal switch to one way or the other with the ignition off. This will break the circuit between the two. If that works you will have to find a way to disconnect the turn signal switch. John