ppc
M Go Blue
Provided that the pin 7 mod has been done.
(5 minute) 7 pin mod also OD in Low mod in 5 minutes. 80 series fzj80 Lx450 (1 Viewer)
- Thread starter GW Nugget
- Start date
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Provided that the pin 7 mod has been done.
I have CDL switch on my 97 LC and haven't done the pin 7 or any such modification. When I switch to 4Lo, the center diff automatically locks as well. If it didn't, what would be the point of the pin7 mod? Having the CDL switch only gives me the ability to lock the center diff in 4hi.
I may be misreading, but that's exactly it. A CDL switch on its own (with no pin 7 mod) only adds the ability to lock the center diff while in high, and nothing more, as you said.
Without doing the pin 7 mod, the center diff always automatically locks when you put it in low & you have no control over that. So, disconnecting pin 7 prevents that automatic lock feature. The purpose is so you can go into low AND have the center diff open... which is nice if you need low range, but are making tighter turns, where it might otherwise bind/scrub with the center locked.
So, with a CDL switch and pin 7 mod together, you have total independent control of high/low & locked/unlocked.
Conversely, if you do the pin 7 mod alone (without having a CDL switch), your center diff will always stay open in high & low, and you won't be able to lock it.
So, only doing CDL switch is fine... and doing CDL & pin 7 together is fine... but you don't want to ONLY do pin 7.
If you don't need an open center diff in low range, don't worry about pin 7. I don't really need it, but I did the mod anyway because it's free, easy, and reversible.
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i'm another person who has added a CDL switch on a '95 but no other pin7 related mods. i do lock the diff in High when on gravel, dirt, or snow. but haven't found a need yet to keep in unlocked in Low, or fool the trans shift points, which is why i haven't done either wiring mod as im undecided on which path i should take.
CDL locks automatically and disabled the ABS in low.
CDL locks automatically and disabled the ABS in low.
alia176
SILVER Star
Oh man, I can't tell you the number of times I was in 2WD with the rear diff locked and struggling to go up something. It finally dawned on me that I forgot to engage the four-wheel drive with the CDL button
.The CDL button has a whole new meaning for those of us who are part-time. Still, I so miss having an actual t case lever to go into four low, like the old days.
ChaseTruck
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And it takes the ABS out. Which I like when driving a dirt road in 4HI.
I have only found a few times where I was really wishing to have the center diff unlocked in 4low. This usually is when making a decent on a steep paved road with lots of switchbacks and I don't want to ride my brakes the whole time and dropping into 2nd doesn't provide enough engine breaking to keep me from gaining too much speed. These are usually very long grades (15-30 minutes) where heating up your brakes by overuse can be a real problem. Changing the shift points might be helpful for me on some dirt roads where there are sections that require the 4low gearing to climb mixed with stretches where you want to go a little faster. The 2nd start button helps some to prevent the frequent rough shift in gears but I am curious if the pin7 pro mod would be noticeably better. Seems like an easy enough modification that is reversible. I've been meaning to give it a shot for a long time but I keep forgetting to do it and then forget about it until threads like this pop up and remind me of how bad a procrastinator I can be
Here in the northeast, we have lots of these things called trees. On tight trails it is extremely beneficial to be 3x open in low range to avoid understeer. It puts much less load on the driveline when crawling around. Plus, I don't want the truck making decisions for me. Every situation is unique.
Since the A343F transmission (95-97) ECM operates the PWR button and 4L differently then the A440F (90-94).
For the A343F (95-97):
When in 4L, the transfer case tells the ECM that that you are in 4L via a voltage of 7.5-14V. That signal commands the ECM to use the 4L map. Interrupting this signal will keep the 4H mapping. You can also accomplish this by adding a switch to wire/pin 9 on connector E7 behind the glove box area. E7 is the connector with 22 pins.
I plan to cut the wire and extent the leads to a switch. The hope is that switch off (signal open) will keep the 4H map which allows the transmission to shift into O/D. When the switch is on (signal to ECM) the ECM would initiate 4L mapping (normal operation).
Just a different way to accomplish the same goal.
For the A343F (95-97):
When in 4L, the transfer case tells the ECM that that you are in 4L via a voltage of 7.5-14V. That signal commands the ECM to use the 4L map. Interrupting this signal will keep the 4H mapping. You can also accomplish this by adding a switch to wire/pin 9 on connector E7 behind the glove box area. E7 is the connector with 22 pins.
I plan to cut the wire and extent the leads to a switch. The hope is that switch off (signal open) will keep the 4H map which allows the transmission to shift into O/D. When the switch is on (signal to ECM) the ECM would initiate 4L mapping (normal operation).
Just a different way to accomplish the same goal.
Why is there a different shift point for H and L? Does the sudden shift point in L reduce wear on the clutches in the AT?
Does the PWR-button switch between the H and L shift pattern? or is there a 3rd shift pattern that the PWR button activates?
Does the PWR-button switch between the H and L shift pattern? or is there a 3rd shift pattern that the PWR button activates?
@ChaseTruck i just did the Pin7 mod in kickpanel and added an OEM CDL switch in my 97. But the switch is not working. (I do get the backlight in the switch). When I go into 4L the ABS light doesn’t come on. My question is does ABS get turned off with the CDL activation? Or is it supposed to go off when in 4L? I’m trying to figure out what isn’t working. CDL worked before I did the mods. Thanks.
The CDL disables ABS when locked. The CDL switch on the transfer case grounds pin A13-19 on the ABS ECU and illuminates the ABS dash lamp.
The Toyota EWD is invaluable when troubleshooting.
Thanks for the data. I’ve confirmed the CDL is not engaging. It worked just before I did this change. So it sounds like something has caused the CDL to not engage (and therefore no ABS light). So I’ll be checking the signal path from this new switch down to the CDL motor. There was a dummy plug in the dash connection C5 with pins 7-10 jumper installed. I’ll check if the switch accomplishes this also. And then check the activate/deactivate signals at the motor? I’m not sure what else could have happened after removing pin 7 from the kick panel controller?
That jumper shorting 7-10 is the same as having the CDL dash switch always on. That's why it auto locks the CDL in low range in the unmolested configuration.
By removing the jumper, replacing it with a switch, and removing C5-7 from the CDL control relay, you now have manual control of the CDL in both low and high range.
ChaseTruck
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We’ve done this on the ‘93 a very long time ago. The one thing I remember is that I almost unpinned the wrong wire because I mistook wire colors under less than optimal lighting in the cramped conditions down there in the kick panel. Better light & focusing on the connector helped doing it right.
Oh s***. You guys are right. I depinned the wrong wire in the dark. It looks black with blue but it’s dark blue. And it’s pin 3. I’ll fix and remove on 7 and update. Cheers.
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