I pulled the Viscous Heater Relay the other day. When I started it up in the morning (cold Engine) I heard a compressor cycling. I figured the temp. control must have been set to defrost. After checking that it was not on Defrost but on floor heat. The AC compressor was cycling. Anybody have any ideas why?

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2006 khaki Liberty Sport CRD - V6 Airbox

170lbs English Mastiff loves whip cream on his treats (it is his jeep too)

Normal. Only face level setting supposedly disables AC cycling in winter.

DOC

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2005 KJ CRD Ltd Detroit TrueTrac Bilsteins G2 GDE "HOT" ECU GDE TCM "Tow Tune" "euro" TC SEGR Weeks Elbow New HG at 130K ARPs Clean CAT aFe Filter Magnaflow Exhaust EHM Cumminos In-Tank Lift Pump Hayden Fan Clutch Nylon Fan VH Enabled with GDE lower shutoff point Recalibrated Temp Gauge Tekonsha Prodigy Sears P-1 ZDDP

Per the Owner's Manual the AC compressor will cycle, regardless of whether the AC button is on or off, when the Climate Control Mode Selection knob (middle one) is set for defrost, mix (defrost and floor), and floor modes. I don't think it cycles in panel or bi-level modes. I don't know for sure about recirculate mode but judging by how quickly the window's fog when heat is on in recirculate mode I'm pretty sure the AC compressor does not cycle.

Pretty much standard for all vehicles for quite some time now. Keeps interior humidity down and occasional running of the compressor keeps seals lubricated in "off" season.

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Sold to LOST member my 05 Ltd, GDE Stg II turbo + TCM tune, SunCoast TC w. Transgo kit, Steiger window regulators, Samcos, Fumoto valve, 2nd gen filter head with Lub. Spec. bleeder, Hayden clutch & 11 blade fan, inverted spare, P-1 battery, BF Goodrich Long Trail TAs, Etecno1 glow plugs, timing belt at 50K miles/8 yrs

Ok, Thanks I only thought it cycled in defrost or when you actually wanted to use the AC. Maybe I'll install a bypass switch to control that.

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2006 khaki Liberty Sport CRD - V6 Airbox

170lbs English Mastiff loves whip cream on his treats (it is his jeep too)

There is a how-to somewhere that shows where to apply a piece of tape in the hvac control unit to keep the AC off until you actually turn it on.

DOC

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2005 KJ CRD Ltd Detroit TrueTrac Bilsteins G2 GDE "HOT" ECU GDE TCM "Tow Tune" "euro" TC SEGR Weeks Elbow New HG at 130K ARPs Clean CAT aFe Filter Magnaflow Exhaust EHM Cumminos In-Tank Lift Pump Hayden Fan Clutch Nylon Fan VH Enabled with GDE lower shutoff point Recalibrated Temp Gauge Tekonsha Prodigy Sears P-1 ZDDP

Scroll down to 'Chessmaster's writeup:

viewtopic.php?t=6042

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How do the machines know what chicken tastes like?

I think i will get a used temp control from a wrecking yard nd try the bypass. This way I'll still have a good one on hand. Thanks

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2006 khaki Liberty Sport CRD - V6 Airbox

170lbs English Mastiff loves whip cream on his treats (it is his jeep too)

Just my but why bother? There are some benefits to running the compressor in some modes to remove humidity and keep seals lubed and if you don't want it to run just use the panel and bi-level modes.

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Sold to LOST member my 05 Ltd, GDE Stg II turbo + TCM tune, SunCoast TC w. Transgo kit, Steiger window regulators, Samcos, Fumoto valve, 2nd gen filter head with Lub. Spec. bleeder, Hayden clutch & 11 blade fan, inverted spare, P-1 battery, BF Goodrich Long Trail TAs, Etecno1 glow plugs, timing belt at 50K miles/8 yrs

I also agree with papaindigo, you have the switch to engage ac whenever you want. Also, many German cars don't even engage ac even on defrost, and if they do, you can manually switch it off. More options is better imo. But its your car, and we obviously just voice some opinions, ultimately choose what is best for you.

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2005 kj CRD, samco, suncoast tc, provent, Kennedy lift pump, GDE ECO full torque, 2nd gen filter head, 245/70/16 a/t tires, mopar light bar, fumoto oil valve, OEM Skid Plates, ARB Front bumper and HD OME, tru cool LPD47391 40k GVW tranny cooler (stock cooler delete), FF Dynamics e-fan and shroud, rocker arms replaced, HDS2 190F thermostat.