• NAXJA is having its 18th annual March Membership Drive!!!
    Everyone who joins or renews during March will be entered into a drawing!
    More Information - Join/Renew
  • Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

89 Transmission Switch ("Power" "Comfort")Question

JeepBoy89

NAXJA Forum User
Location
Orange County
I have been told that everone leaves that setting on "POWER" ? i would like to do that as well but i cant tell if my switch is not working or the light is just out LOL if the light is not coming on when i switch it what should i check ? i dont think the switch is bad tho ... ? but who knows can someone give me a idea on what i should check so that i can use the switch and set it to power ofcourse LOL. THANKS GUYS FOR ALL YOUR HELP!!!!!!!!
Shaun A.
 
The best way to check is to get out on some place where you can accelerate from a standstill, stop, then do it again a couple of times. The power switch should make a difference in the shift points and in the feel of the shifts when you accelerate moderately, but it isn't as much difference when you floor it. If you push it hard, it will take off pretty well in either setting. I usually left my 87 on "comfort," figuring that when needed I could just goose it.
 
In my 1989 MJ I too leave it in "comfort" setting. More for mileage than any other reason.

Test it on a moderate hill on the free way. If you feel the jeep "lugging", dont move your right foot, switch from comfort to power and the tranny will (should) imeadeaty down shift.

CW
 
Pin C11 at the TCU gets 12V in Power mode. If your switch is broken, or you want to use the power/ comfort switch for a different purpose, wire it accordingly.
The schematic I'm looking at now calls out fuse F3 for the switch. There's also an inline fuse near the TCU, but that's not your culprit.
 
Last edited:
cwlongshot said:
In my 1989 MJ I too leave it in "comfort" setting. More for mileage than any other reason.
Interesting, considering that the "Power" setting calls for firmer shifts and less slippage. The Power setting should produce better gas mileage than the "Comfort" setting. I think the real difference is in how the right foot is applied to the skinny pedal.

Also, the firmer shifts in the "Power" setting helpt the tranny to live longer. Less slippage = less heat.
 
Eagle said:
Interesting, considering that the "Power" setting calls for firmer shifts and less slippage. The Power setting should produce better gas mileage than the "Comfort" setting. I think the real difference is in how the right foot is applied to the skinny pedal.

Also, the firmer shifts in the "Power" setting helpt the tranny to live longer. Less slippage = less heat.

I've noodled with the power/comfort switch for many years and over 180k miles I myself put on the '89 so far. It does use more fuel in POWER than COMFORT setting and the only thing I can figure is more RPM = more fuel. In general POWER mode lets the engine rev higher and downshift more readily for the same throttle position thus increasing the average RPM over a distance travelled. I also don't think longevity is much of an issue since my AW4 has over 260k miles on it with the majority of that being comfort mode.

Somebody contributed the voltage check procedure. It's really simple to run-down if you follow that.
 
Back
Top