ok.. just to get a definitive answer... after searching and coming up with 3 seperate ways to reset the pcm...was wondering what works well for everyone else... iv always done is disconnect the batt cables (both) and turn the ingition to on on/run position for like 20 mins then offf then hook the batt back up..

the reason why i ask is b/c mainly if you install a 180* thermo the PCM should be relearned shouldnt it? i ask this becuase if the stock t-stat is 195 deg. (i think it is atleast) then the computer thinks the motor is still cold untill the temp reaches 195 degs..and if the pcm thinks the motor is still cold (or the ECM..not sure witch one cotrols and moniters it) itll dump extra fuel into the injectors trying to warm up the motor.. well if motor doesnt reach 195* ever b/c of the new 180 thermo then itll continually dump exttra fuel in the injectors resulting in crappy mileage...

just wanna make sure im thinking on the right track... or maybe im way out in left feild

 

im not to sure it burns more gas to make it come up to 195.. i think it just allows the engine to circulate more coolant threw the engine to keep it at 180 degrees.. but thats just what i think... i dont know anything at all about them but i think its pretty much whats in semi's.. when climbing a hill the temputure comes up alot till something clicks over at a certain temp and cools the engine back down.. i think the thermostat lets coolant threw when it gets above 195 degrees..

 

well ive always dun basically the same thing i disconect both batt cables then turn on the headlights (i dont turn the ignition) he it sit for a good half hour the go hook it all back up. i think thats more to reset it thow hot have it relearn stuff thow if you do that id think it wouldent know there is a diffrent thermo it was programed for a 195 so id think it would still think that untill it ran with it for a while and relised that everything else is running good then accept the new opp temp just my thoughts...

 

20dodgeram01 That Click you are hearing in your semi is the computer turning on the engine fan. Most of them have a clutch like an
ac compressor and a solenoid to engage them.

shott8283 I have always done it exactly how you describe it and it works for me.

 

ok cool...ill just leave it alone... my next question is say your doing electrical work and just disconnect the battery ( like i do every weekend pretty much) w/o turning the ignition...does this reset the pcm? just curious... i wish the manual/s had a section in there on reseting the pcm

 

if its disconetected longenuf it should there are cappasaters in there for the airbags so there is susposto be a little power for 3 min after the bat is discoleted so if your in an accident and your bat gets disconeted oe dammaged there is still power to set off the air bags

if your comp is getting reset every weekend that could be why its not relearning the new temp. now this is just my understanding of the comp i agree there should be a section on how it works.... wen you disconect the batt the comp is reset not relearning everything from the factory its programed to run at around 195 degs you want it to run around 180 degs so wen you have been driving it for a while (dont know how long) it "figures out" that its not going to get over 180 so it starts adapting to that temp so its not burning as much fuel ect to try and warm up. now wen you unhook your bat your comp is being reset do that wen you re-hook up your bat the comp has "forgot" what it learned about running at 180 degs and thinks its susposro be at 195 again so it has to go through the"figuring out" process again

now you can get batt disconects that you replace your outher bat lugs with they have a *** on the top that you just turn to turn off the power but they also come with a fuseable link that you bypas this with (its susposto be on the neg side) so you hook 1 side of the fuse link to the bat before the switch then the outher you ground to your truck and i belive it has a 5 amp fuse in it so it will keep your eletronics set but if you short something or try to start it it will just pop that fuse

BATTERYMASTERSWITCH
$ 3.88

[IMG]local://upfiles/27664/DF279DFA7807483D8876EB28B2FD9F12.gif[/IMG]


• For top post batteries
• Attach to negative battery post
• 1/4 turn of **** disconnects battery to prevent drain or remove **** to prevent theft
• Rated: 100 amps continuous 600 amps cranking (you might need a bigger one for your 136 alt)
• Includes fused power by pass wire


Weight: 0.4 lbs

again thats just my 2 cents worth lol

 

that might be my otion.. either way i really cant get around disconnecting the batt b/c every now and then ill weld something and your seriously need to break the enitre circuit when you weld on a vehicle..i really wish i could program the op temp using the hypertech... guess they didnt think of that... oh well...gotta live with it i guess

 

we have a thing at work its called an antyzap i think its made by mac you clamp one side on the + and the outher on the - on the bat then you can weld without unhooking it. i dont imagen its cheap thow and its susposedley even safer than disconecting the bat but atleast with the on off disconect you wouldent half to unhook the bat as often. i done even know for shure if thsts how the comp opporates exactley just what i always thought

 

no kidding... ill look it up

http://cgi.ebay.com/ebaymotors/AntiZ...QQcmdZViewItem

 

thats it... alot cheaper than i thought even looks exactley the same ill have a look tomorow at the brand or ours...maby its not mac lol