I removed the solenoid from the diff to eliminate any variables associated with tooth alignment between the solenoid and the locking fork.

</font>

• <font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">With the dash switch in the off position, I slide the fork (by hand) to the unlocked position and the solid green light is off. GOOD.
  </font></li>
• <font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">I move the fork into the locked position and get a solid green light indicating the diff is locked. GOOD.
  </font></li>
• <font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">I now put the dash switch in the on position with the diff locked and get a blinking green light. NOT GOOD.</font></li>

<font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">I can't explain why, but RLP cannot be used in conjunction with an LED to indicate the diff is in the locked position. I give up...I will just put up with the blinking green LED... <img border="0" alt="[Baby]" title="" src="graemlins/baby.gif" />

</font><blockquote><font size="1" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">quote:</font><hr /><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">Originally posted by YourMom:
<strong>I suppose the limit switches will prevent the motor from jamming like Carl Whitmore experienced...good idea.
</strong></font><hr /></blockquote><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">I might be mis-reading this, but I've never had either of my actuators jam.

</font><blockquote><font size="1" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">quote:</font><hr /><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">Originally posted by YourMom:
<strong></font></li>[*]<font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">I now put the dash switch in the on position with the diff locked and get a blinking green light. NOT GOOD.[/list]I can't explain why, but RLP cannot be used in conjunction with an LED to indicate the diff is in the locked position. I give up...I will just put up with the blinking green LED... <img border="0" alt="[Baby]" title="" src="graemlins/baby.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">This is with the electric/motor disconnected from the diff? Are they both grounded to the same source? Basically, are you using a common ground for the electric motor, and the locking sensor in the diff?

</font><blockquote><font size="1" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">quote:</font><hr /><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">Originally posted by YourMom:
<strong>Mike--my locker is from a '98 Limited and has no springs whatsoever. With the solenoid removed, I was easily able to slide the fork mechanism between the locked and unlocked states. I also operated the motor while it was detached from the diff--hit the diff lock button, the gear on the end of the motor would turn about 1/2 a revolution and stop--hit the diff lock button again and the motor would turn 1/2 a revolution in the other direction and stop. The process takes just under 1 second. You'll be sorry if you run the motor without the limit switches hooked up.

I also found that the diff lock indicator switch would light up the locked light when the locker was only about 3/4 of the way locked.</strong></font><hr /></blockquote><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">Thanks for the info Ken. Yes, I am definitely using the limit switches. I am aware of the folly of doing otherwise. This diagram shows how I wired my locker. My question is: Why pulse the motor?

Before I installed my locker, I hooked it up and checked out how the mechanism moved. I didn't see any springs either, and I assumed that there was a fixed relationship between the position of the motor and the position of the splined sleeve that locks the side gear to the ring gear.

In actual use, however, the motor always runs to the limit switch and stops (I have an indicator light that shows the state of the limit switches, plus I can hear the relays click off), but, the locker usually doesn't lock/unlock (as indicated by the locked-indicator switch) until I drive a short distance. Sometimes it will lock/unlock instantly if the splines happen to be lined up correctly.

This tells me that the electric motor does not have absolute control over the state of the locker, and thus there must be some sort of spring-loading going on somewhere, whether by design or by abuse. Perhaps the way I have it hooked up is incorrect and I am abusing the poor motor. Karl's writeup mentions using resistors to slow the motor down so it doesn't jam. I haven't ever had my motor jam except for when I was first playing with it before I put it in and neglected to use the limit switches.

My locker is for a 97 4Runner. My locked indicator switch will only close when the locker is fully in the locked position (perhaps you are off a tooth or two). Perhaps there are variations in the design of these lockers?

<small>[ 10 April 2002, 10:56 AM: Message edited by: thecarterman ]</small>

</font><blockquote><font size="1" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">quote:</font><hr /><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">Originally posted by I Lean:
<strong>I might be mis-reading this, but I've never had either of my actuators jam.</strong></font><hr /></blockquote><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">Sorry, it was Mike Carter's article that brought that issue up.

</font><blockquote><font size="1" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">quote:</font><hr /><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">Originally posted by Karl:
<strong>This is with the electric/motor disconnected from the diff? Are they both grounded to the same source? Basically, are you using a common ground for the electric motor, and the locking sensor in the diff?</strong></font><hr /></blockquote><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">Yes and Yes. The two white-black wires coming out of the diff (one is ground for the detection switch and the other is ground for the limit switches) are soldered together and grounded in the same spot as the ground for the ECU. This is exactly how the factory does it according to the wiring diagram I posted above.

Mike, the pulsing thing has me confused too. The motor will run continuously in either direction until the limit switches are triggered. However, the 'RLP' obviously sends 1 second pulses--otherwise my LED on the dashboard would not be flashing.

There is something on the wiring diagram I posted above that all of us are missing. As I mentioned before, the position of the dash switch should not affect operation of the diff lock detection switch and the LED that is hooked to the same circuit.

I think this is the solution. The red is how it is hooked up now and the blue is how I propose to hook it up. The LED will only get power when the diff lock switch is engaged and won't illuminate until the diff lock detection switch closes completing the circuit to ground.

<img src="http://home.off-road.com/~kemanuel/forum/WTF2_thumb.jpg" alt="" />

Click here for a larger, more readable picture.

</font><blockquote><font size="1" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">quote:</font><hr /><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">Originally posted by YourMom:
<strong>I think this is the solution. The red is how it is hooked up now and the blue is how I propose to hook it up. The LED will only get power when the diff lock switch is engaged and won't illuminate until the diff lock detection switch closes completing the circuit to ground.

<img src="http://home.off-road.com/~kemanuel/forum/WTF2_thumb.jpg" alt="" />

Click here for a larger, more readable picture.</strong></font><hr /></blockquote><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">I am not 100% sure what to make of the J7 Junction Connector because my '86 wiring diagram doesn't use this type of symbol. But I assume that it is showing that all 4 wires tie together at this point.

Regardless, it does not appear that RLP pulses the motor. I am not sure what it does, but it sounds like it serves a role in blinking the LED and perhaps allowing the Diff Lock ECU to detect when the Diff is locked (however if the limit switch has been reached, I don't see why the Diff Lock ECU would care).

I would guess that the RLP probably alternates either between 0v and ground (blinking the LED while the Lock Detect Sw is open) or between +12v and gnd (both blinking the LED and allowing the Diff Lock ECU to detect when the Lock Detect Sw closes). I would guess that the ABS ECU is looking for a constant ground so that it knows when the locker is locked.

Your second diagram (blue) looks fine to me, with the exception that I'd hook the LED to a constant +12v power source rather than behind the Control Switch. It will work either way, but hooking it to constant 12v will allow the LED to function independently of the Lock Control Switch. This is how the Factory diagram shows it wired. For example, if you turned off the Lock Control Switch, but the locker didn't disengage for some reason, you'd still want the LED to remain lit so you would know that it was still locked.

I was trying the 3 indicator light system shown on Karl Bellve's write up. Then I scrapped the extra 2 LEDs. My relays had 8 contacts so I may have messed up there. I also think the motor was jammed by whoever pulled it from the junkyard. I didn't bench test it. I should have.

Carterman, What relays are you useing? Normal headlight relays? I'll try again with different relays after I leave town for a week. I need a break from this.

Thanks for the diagrams everyone. I'll get it soon.

<small>[ 10 April 2002, 02:56 PM: Message edited by: jx94148 ]</small>

</font><blockquote><font size="1" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">quote:</font><hr /><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">Originally posted by thecarterman:
<strong>Regardless, it does not appear that RLP pulses the motor. I am not sure what it does, but it sounds like it serves a role in blinking the LED and perhaps allowing the Diff Lock ECU to detect when the Diff is locked (however if the limit switch has been reached, I don't see why the Diff Lock ECU would care).</strong></font><hr /></blockquote><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">I am with you on that one. I believe the diff lock detection switch is only used to light up the light on the dashboard and perhaps turn off the ABS. When I was running the motor while it was separated from the diff, the motor would turn both directions whether I had the diff lock detection switch open or closed. This tells me that the limit switches, NOT the detection switch, have sole control over the motor's operation.

</font><blockquote><font size="1" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">quote:</font><hr /><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans"><strong>
Your second diagram (blue) looks fine to me, with the exception that I'd hook the LED to a constant +12v power source rather than behind the Control Switch. </strong></font><hr /></blockquote><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">Fair enough. I can merely tap the +12V wire before the dash switch rather than after (the way it is drawn above).

This method seems fail-proof, but I never would have guessed that RLP sends those crazy pulses!?! I just assumed that the only time current would be passing to the rear differential is when the locker is changing states. Obviously not the case. I will hook up the volt meter to all six wires (at the diff) and see if they are getting power at times other than when it is locking/unlocking.

This has been a great thread! Thanks guys!

</font><blockquote><font size="1" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">quote:</font><hr /><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">Originally posted by jx94148:
<strong>
Carterman, What relays are you useing? Normal headlight relays? </strong></font><hr /></blockquote><font size="2" face="Verdana, Tahoma, Arial, Helv, Helvetica, Sans">The circuit I built uses N.O. (Normally Open) DPST (Double Pole, Single Throw) relays.

Double Pole simply means that each relay has two separate switches in it that open and close in unison (contrast with Single Pole which only has one switch).

Single Throw means that the switches have an On and an Off position. (Contrasted with Double Throw switches which have two different On positions). Note, you can always use a double pole switch as a single pole switch, simply don't use one set of contacts.

Normally Open means the the switches are normally in the Off position unless the relay is activated.

I used two of these minuature relays from RadioShack.com. They are small and are meant to be soldered to a circuit board, which is what I was looking for, however, just about any Double Pole (DPDT or DPST) relay with a 12v coil that will handle around 5amps will work.

The Bosh-style headlight relays are typically SPDT. They won't work with the way that I wired my locker.

However, you can use them. I was originally going to use headlight relays. This is how I was going to wire them up.. This diagram is very similar to the first, but the current for the motor goes through the control switch as well as the relays, and the control switch needs to be a DPDT switch as it is used to reverse the polarity. This won't be a problem as long as you use a decent switch. I doubt the locker motor even draws all that much current. I haven't tested this diagram, but it should be valid.

<small>[ 10 April 2002, 04:20 PM: Message edited by: thecarterman ]</small>