A couple months ago, when I started my truck I noticed the temperature reading in the overhead console read -40F when in reality it was more like 50. After I went down the road about 5 miles, it started counting up abotu a degree every second until it reached the proper reading. Took it to the dealer and they replaced a "pigtail" (whatever that is) and haven't had any problems since yesterday when I looked up and noticed it said -40F again [:@] Parked the truck, turned it off and stared it again and the temp read 54 (normal). Has anyone else come across this?? I'm headed back to the dealer tomorrow to see what's up.

 

-40 is the default, it also is where Celcius and Fahrenheit equal each other. -40 Degrees C is the same temperature as -40 Degrees F. The temp sensor has max resistance when at -40 or colder. Max resistance is the same as saying open circuit. It sounds like you have a problem with the ambient temp sensor. The pig tail is the short jumper wire between the temp sensor and the headlamp wire, which you should not have (94-01). So forget about that comment from the dealer.

 

Had the same thing on my '06 once about 3 months ago. Started at -40 and counted up to the correct temp. Hasn't happened again since, at least not that I've noticed anyway

 

My 06 did the same thing twice but has cleared up on its own.

 

According to the service manual and my dealer, the outside temperature is sampled periodically after the vehicle has been running for awhile. This avoids an initial high reading if the truck has been sitting in the sun. Mine always starts at a low value and then creeps upward for awhile. Then it stablizes. I've compared its readings with a refridgeration therometer held outside the door. The overhead reading is usually within a few of degrees of actual after I've been driving for a few minutes.

Roger...

 

this just happend to my buddys 06 he just picked up from the dealer yesterday... i was intalling his system and after turning the key on and off like 10 times checking for a switched power source i noticed that goin on too... it went away after a bit

 

The temp sensor is located in front of the A/C condensor radiator (in board of left headlamp). Temp readings are not taken when the vehicle is not moving unless it has been sitting for somehting like 12 hours, then it will take a reading. Once you start driving, the temp readings are a function of speed and time. This is to prevent reading heat from the engine if you happen to stop at a red light. It is normal for the trip computer's temp reading to be off when you first get in the vehicle, but not sitting at -40 Degrees (unless the vehicle was subjected to -40 degrees while sitting).

 

Mine has started to do this as well? Anyone find a fix? My 2001 Grand Caravan Temps is allways correct.

 

My 05 has never done this, must be just reserved for the 06....