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Trystane
12-05-2013, 11:13 AM
It was a tad bit cold this morning here in Wyoming. -21F to be exact and I noticed a few things that didn't happen yesterday when it was only -5.

When the engine first turned over I noticed that the lights on the shifter were flashing. They probably flashed for about 5 minutes while I scraped off ice and when I got back in the car it had stopped.

The hydrolics in the hatchback barely work as I had to hold up the hatch to get my scraper out. Not a big deal and I'm not even sure if there's anything to do about it but I did want to point it out.

My biggest concern is the shifter and if that's expected behavior at such temps, an oddity to be dismissed, or a sign of things to come?

tknospdr
12-05-2013, 11:26 AM
I have nothing at all of substance to add to this thread (I live in Florida and it's gonna get to 81F today).

But when I read your thread title I remembered the movie Liar Liar and just snickered a little. :)

msjulie33
12-05-2013, 11:35 AM
-21 is pretty cold! I'm from New England and it can get plenty cold there, but I don't remember that cold... maybe the lights were to warn you about the temp? We had an older Audi that refused to shift out of 1s gear when it was super cold and supposedly that was a feature to warn you the car really wasn't ready to drive faster than a slow crawl out of the drive way. Hmm...

MrFiat
12-05-2013, 05:23 PM
It was a tad bit cold this morning here in Wyoming. -21F to be exact and I noticed a few things that didn't happen yesterday when it was only -5.

When the engine first turned over I noticed that the lights on the shifter were flashing. They probably flashed for about 5 minutes while I scraped off ice and when I got back in the car it had stopped.

The hydrolics in the hatchback barely work as I had to hold up the hatch to get my scraper out. Not a big deal and I'm not even sure if there's anything to do about it but I did want to point it out.

My biggest concern is the shifter and if that's expected behavior at such temps, an oddity to be dismissed, or a sign of things to come?

Do you have an early 500 ? On the early cars, Fiat employed an oil viscosity sensor which limited cold starting behavior. The multi-air engine relys heavily on hydraulics to run the valve system, so the early cars would (by design) not start/run at temps below -25 degrees C (-13 deg. F.) A block heater was used in those situations. However, I believe they might have deleted that system from the later cars.

The following is a description of the sensor and related system, complements of Chrysler, via our Admin, Chis V.
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When ambient temperatures goes below -25C (-13F), the viscosity sensor was used by the engine management system to help determine the operational strategy of MultiAir. However, after continuous testing (in the Arctic, no less), it was determined it wasn't needed and subsequently deleted off of later production vehicles.

It is an interesting device and I've included how it worked in the description below.



When the oil temperature is between -25C (-13F) and -35C (-31F), the engine management system will use the signal from the viscosity sensor to determine the oil viscosity level. If the engine management system determines that the oil viscosity is too low (thick oil), the glow plug light on the instrument panel will flash and a text message appears on the EVIC telling the driver to warm the engine (Canadian cars have a block heater as standard equipment).

During extreme cold starts, colder than -35C (-31F), the engine management system will prevent the engine from starting. In this extreme cold condition, the glow plug light on the instrument panel will flash and a text message appears on the EVIC telling the operator to warm the engine (Plugging in the block heater takes care of this).

The viscosity sensor measures the viscosity of the oil with a tuning fork shaped sensor that uses vibration to measure the viscosity. The tuning fork is vibrated at a set frequency for a determined amount of time. When the vibration from the sensor is turned off, the vibration of the sensor that is caused by the surrounding fluid is monitored. The frequency and rate of change of the vibrations reflects the viscosity of the fluid.

There are multiple components contained within the viscosity sensor. In the sensing end (immersed in the oil) is the tuning fork sensor and a thermocouple sensor. These sensors are attached to an integrated circuit (IC) board in the body of the sensor which monitors the sensors. There are two more IC’s in the sensor that provide power management and an output from the viscosity sensor.

The viscosity output from the sensor is provided to the PCM as a hardwired input. The output is a pulse width modulated (PWM) signal that the PCM will recognize and translate into a viscosity value. The viscosity sensor can also provide a temperature output as a PWM signal but at this time, the temperature signal is not used.


description courtesy of Chrysler

szmwpqvz
12-05-2013, 07:08 PM
We bought a 500L back in August and this same thing started to happen in October. It's been to the dealer several times for diagnosis and finally the ordered a shifter for it. The part has not arrived yet. It seems that their is obviously a known problem with the shifter. I don't understand how Fiat did not catch this during cold weather testing. If you do a search of the forum, you will find others with the same problem.

Tweak
12-05-2013, 08:39 PM
We bought a 500L back in August and this same thing started to happen in October. It's been to the dealer several times for diagnosis and finally the ordered a shifter for it. The part has not arrived yet. It seems that their is obviously a known problem with the shifter. I don't understand how Fiat did not catch this during cold weather testing. If you do a search of the forum, you will find others with the same problem.

Welcome to the forum.