2014 JGC (WK2) 5.7L Fan issue

[PeterK821]

It appears that reprogramming the engine fan temps doesn't really work. I can set the new AC ON/OFF LO/MED/HIGH temps, but when I do, it appears to have absolutely no effect. I take that back...it seems to have SOME effect the first time I run the vehicle after making the changes, then...never again. The fan comes on at the same temps as before.

Now, this is with the HD cooling option (trailer tow package) which uses a PWM controlled fan. Does the fan speed control only work with the standard LO/HI switched non-HD cooling fan?

[mikel]

odd, we'll have to look into this.
Can you post the last tune written with the fan changes made?

Thanks

[PeterK821]

I'll have to see about getting it uploaded. I was using the "modified stock tune" at the time -- I'll see if it makes any difference when using one of the others. It is actually really weird because it seemed to work when I would first write the new values (I have a licensed WiTech scan tool) but...even then it was weird. Here's what I would see:

The tool (and presumably) vehicle defaults are in parentheses:
Wrote the following values for A/C OFF fan operation:
Fan LS Low: 205 (Default: 222.79)
Fan MS Low: 210 (Default: 222.79)
Fan HS Low: 210 (Default: 222.79)

Fan LS High: 205 (Default 219.79)
Fan MS High: 210 (Default 222.79)
Fan HS High: 210 (Default 222.79)

A/C ON fan operation:
Fan LS Low: 200 (Default 219.79)
Fan MS Low: 205 (Default 375.79 -- yes, this is what is listed as the default)
Fan HS Low: 205 (Default 222.79)

Fan LS High: 200 (Default 219.79)
Fan MS High: 205 (Default 375.79)
Fan HS High: 205 (Default 222.79)

I'm not sure why the defaults have the ".79" but that's how they are listed. To get round numbers you have to increase the values to 230 which then stays as a round number as you decrease back to the temp you want. It was really weird to see "375.79" as the A/C ON low speed MS fan default, but that's what it is.

So with the A/C OFF and at idle without the changed values (stock), I monitor coolant temp and the requested fan PWM as this is the HD cooling which does not use the fan HI and fan LO switches. The fan PWM "off" state is around 10.19% (it never goes below that--the fan doesn't spin at this value). At idle, the coolant temp slowly rises to just above 222 degrees, and the fan PWM begins to rapidly ramp up, going from base (10.19%) to 20%, 30%, then 40.15% in the span of about 15 seconds. The temp starts to come down quickly and at around 218 the fan starts ramping down again, reaching "off" again within about 15 seconds. The coolant temp at this point is around 210. Then, of course, the cycle starts over.

Okay, so I flash the modified stock tune properly with the new fan values. I start the vehicle and monitor again. On this first run, the same thing as above happens, EXCEPT the fan starts ramping up at a coolant temperature of around 215 degrees instead of waiting to 222. This doesn't seem to be related to the values I wrote, but it is a difference. This is consistent for the entire test time. HOWEVER, when I leave the vehicle to sit for a while (and hour or so), the fan is back to operating the way it was before the tune. Re-flashing the values again makes it behave differently again...until it sits for a bit and then its back to the way it was.

Weird indeed. The default values being as they are is strange, and the fact that putting new values in changes the behavior (though it doesn't really directly relate to the values programmed)...but only that run time...is really weird.

I'd love to be able to control the fan turn-on temps on this thing -- what do you need to figure this out?

[klein1j]

odd, we'll have to look into this.
Can you post the last tune written with the fan changes made?

Thanks

I have the same exact issue!! I will post my last tune in the morning. I was just on here to start a new thread... What do you know some else has the same issue.

[klein1j]

Attached is my last written tune. The FAN parameters have no affect after initial drive.

Maybe this is related to the following:
-Ambient Temperature.
-2nd set (backup) of default values being restored on second start (almost like "last known good backup")

[klein1j]

Any update?
My last tune was attached to this thread.

[PeterK821]

I don't think it's ambient temperature. Backup values...maybe. But...it definitely behaves this way. The values don't directly affect the cooling fan operation, and after the first time the PCM seems to ignore this and use its default behavior.

[mikel]

we're investigating this.

[klein1j]

we're investigating this.

Thanks, looking forward to a fix.

[klein1j]

After adjusting the fan temps, my "Auto Dim High Beams" feature no longer works. Additionally, a beep (similar to that of the "park sense") comes on about 5 - 10 seconds after starting the vehicle.

I'm not sure if the fan temps are linked to this issue or they are just arising after having the tune applied for some time.

I tried restoring the backup and it initially failed as it could not restore the tire size. This is another issue which requires me to do a very weird sequence which I have not yet made sense of. However, after entering the original tire size, it must fail to update after entering it in for the side wall and then tire height. Then (I think) if you enter the sidewall again after that it it successfully updates. Only after that will the original backup work to restore all including the tire size. but even then, my "Auto Dim High Beams" feature no longer works, and the weird beep is still present.

3 issues are:
1) Fan Temps
2) Auto High Beams.
3) Tire size always takes multiple attempts to work (from 10 - 20 times).

Please help...

[klein1j]

Any update as to what the issue might be, and to when we can expect a fix?

[PeterK821]

I'd love to know when the fan issue will be corrected as well. Would really love to be able to successfully use that feature.

[klein1j]

Can we get a reply? Some detail as to where we are with this, what we think it might be, an ETA etc...?

Silence does not help and only grows frustration....

[klein1j]

Hey Guys, Any update?

Also, is there anything I could do to get my Auto High Beams to work again; calibration update, etc...?

I don't get the high beams enabled message any longer and get an odd beep about 20 seconds after starting the car (Park Sense type beep). I've tried everything from disconnecting the battery for 24 hours, to driving over 25 mph and toggling the switches back and forth, but no go.

May be worth noting I usually get all the PCM and TCM updates when available. I did notice this happened shortly after getting the following 3 TSB 's applied and then reloading the 93 oct tune... This was also around the time when I adjusted the fan parameters.

http://www.wk2jeeps.com/tsb/tsb_wk2_0801714.pdf
http://www.wk2jeeps.com/tsb/tsb_wk2_0800214.pdf
http://www.wk2jeeps.com/tsb/tsb_wk2_2100414.pdf

[ChrisUCF99]

If you just do a canned tune, does everything function? Is it only after stepping outside the canned tune when you start seeing the issues? I applied the 91 canned tune to my 2014 and everything continues to function like it should.