on hot days at normal operating temp my voltage sits at a measly 13.6v. in the winter time, my voltage sits right at or a bit above 14v. i have the towing package so it came w/ a 136 amp alt then i upgrade to the 150amp 5.9er alt. i have a decent sized audio system, runnin a red top under the hood and stinger battery in the rear so they can handle higher voltages fine.i wanted to know if anyone has ever hacked one to give a "colder" reading.

7/8/2007 2:31:40 AM

i thought your jeep was a pre 96? i'm not aware that they had a batt. temp sensor until obdII came in 96, and iirc it might have even been 97 until they got them.

anyway, if you do have one i'm sure it could easily be hacked with a resistor. what number you would need, i have no idea. i'm sure you could get the neccessary data from a fsm (factory service manual) or possibly even a haynes/chilton manual. relocating the sensor to somewhere it's going to see lower temps could be an option also.

7/8/2007 2:46:30 AM

yea it's '95 , do they not have sensors?? i know they don't have voltage regulators so it has to be done through ecu right?

7/8/2007 2:58:41 AM

yeah, it's definitely regulated through the computer. i just wasn't sure if they incorporated a temp sensor into the mix until obdII, but it's definitely possible they did before then.

seems i do remember dealing with one on an early 90's xj years ago. it would make sense being that you notice an obvious change in voltage with changes in the weather.

7/8/2007 3:26:54 AM

You sure you got the amperages right? I'm about 95% certain stock was 90, there was a 110 option, and 5.9's came with 136.

7/8/2007 3:48:02 AM

yea there's the regular 90 then 136 if u got the towing package then 150 on the 5.9 for the nice electric fan, heated seats etc.

i think i'll have a look see tomorrow to see if i can find the temp sensor then i guess i'll throw it in some ice and measure the resistance to find my resistor value.

7/9/2007 12:36:50 AM

Dude, 0.4 volts isn't a big deal. Not worth it. The guage could just be off for all you know.

7/9/2007 1:47:36 AM

it becomes a bigger deal when it's sitting at 13.6 and i crank my stereo with the a/c on, and the shit drops to 12.8v. i'd rather have my amps seeing higher voltage since the heat means they see even less power than what i'm gettin at the battery. esp since i could be getting 14 or more volts. the gauge is pretty close to what i've gotten on my multimeter.

[Edited on July 9, 2007 at 2:29 AM. Reason : .]

7/9/2007 2:25:47 AM

you could just go with an internally regulated one wire alternator and eliminate all that crap

7/9/2007 10:40:13 AM

^ yes

7/9/2007 1:22:34 PM

or save about $150 and do this

7/9/2007 11:12:58 PM

there is no temp sensor on there, just a field driver from the ecu, the dark green/ black wire is hot from the shutdown relay, and the dark green wire grounds the field through the ecm to control the voltage, you can ground the green wire to make it charge wide open, but be ready for 16v+, or get an adjustable voltage regulator and hook it in

7/10/2007 8:07:17 AM