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Discussion Starter #1
My tranny coolant temp remains below normal limits (in the blue) despite all other fluids being fully warm. This is a new "issue." Thoughts anyone?

P.S.-full service was performed on the transmission <5K miles ago and it has performed flawlessly until now.
 

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If everything mechanically performs normally I would think the temperature sensor and/or its wiring is the issue. Vehicles are rolling computers these days and as such more often the electronics are the root cause.
 

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If everything mechanically performs normally I would think the temperature sensor and/or its wiring is the issue. Vehicles are rolling computers these days and as such more often the electronics are the root cause.
And one conclusion to this is always check the battery first!!!
 

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There are a lot of voltage sensitive sensors in a modern car. A weak battery can cause the sensors to give erratic information to the computers and create false readings. Same with bad connections (check your grounding wires).
 

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I had a similar issue (engine temp almost never went up to normal operating temp) and in the end, it threw an engine check light.

After the thermostat & hoses were replaced, everything is now fine.
 

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Can you give a little more of an explanation? What’s the ambient temp out? Are you driving in Sport or Sport+ and getting on the car and it still isn’t coming up to temp?

If you drive in C mode and drive non aggressively, the trans takes a long time to warm up to 120*(temp where blue goes to white). I took off on a highway cruise in like 30 degree weather recently and threw on distronic at about 75mph and the trans was at 118* and still blue after probably 20-30 miles. Getting on it though and driving with some spirit temps get where they should.
 

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Discussion Starter #9
There are a lot of voltage sensitive sensors in a modern car. A weak battery can cause the sensors to give erratic information to the computers and create false readings. Same with bad connections (check your grounding wires).
Ahhhh. Thank you. Main battery replaced <1 yr ago.
 

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Discussion Starter #10
I had a similar issue (engine temp almost never went up to normal operating temp) and in the end, it threw an engine check light.

After the thermostat & hoses were replaced, everything is now fine.
Same here (thermostat only.)
 

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Discussion Starter #11
Can you give a little more of an explanation? What’s the ambient temp out? Are you driving in Sport or Sport+ and getting on the car and it still isn’t coming up to temp?

If you drive in C mode and drive non aggressively, the trans takes a long time to warm up to 120*(temp where blue goes to white). I took off on a highway cruise in like 30 degree weather recently and threw on distronic at about 75mph and the trans was at 118* and still blue after probably 20-30 miles. Getting on it though and driving with some spirit temps get where they should.
I live in Dallas so ambient temp varies 30-40F in any given 24hr period. I usually drive on the toll roads in C mode and never in my almost 4 years of ownership has it ever taken so long to come out of the blue (which it will do eventually.)

Everything is functioning properly otherwise-this is just a new "issue" for my ride.
 

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Can you give a little more of an explanation? What’s the ambient temp out? Are you driving in Sport or Sport+ and getting on the car and it still isn’t coming up to temp?

If you drive in C mode and drive non aggressively, the trans takes a long time to warm up to 120*(temp where blue goes to white). I took off on a highway cruise in like 30 degree weather recently and threw on distronic at about 75mph and the trans was at 118* and still blue after probably 20-30 miles. Getting on it though and driving with some spirit temps get where they should.

This has been my experience as well, being in Denver, CO area, I am usually starting at 50* or so with the garaged kept car, and it takes some time and a number of miles to get up past the 120* or so mark. And it will attain temp more quickly with "spirited" driving. :D I try and wait on doing that until I at least get past the 80-90* temps.
 
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