AMBIENT TEMP INDICATOR
Thread Starter
Senior Member
Joined: May 2008
Posts: 477
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From: Maricopa, AZ
2012 S63, 2013 E350 Bluetec
AMBIENT TEMP INDICATOR
The outside temp indicator on my 05 C230 consistently reads 2 degrees hotter than what the actual temperature is. Is there anyway to have this adjusted?
Thread Starter
Senior Member
Joined: May 2008
Posts: 477
Likes: 30
From: Maricopa, AZ
2012 S63, 2013 E350 Bluetec
Agreed; however, I have a friend with an '07 C230 that reads two degrees lower than my car even if we're driving side-by-side; and my other car also reads two degrees lower than my MB.
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From: WNY
2005 w203 C230
My wife's 2005 C230 is TODAY reading [-40] when it is +80 outside. I recall this is a BAD ambiet / outside temerature sensor (located under / near the curb side fog light)...
Is this true? Bad sensor?
Thanks,
Jake
Is this true? Bad sensor?
Thanks,
Jake
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Joined: Feb 2006
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From: WNY
2005 w203 C230
Upon inspection, loose inspection with a flashlight, looking under the sensor...it appears that the actual grounding wire has pulled out of the connector! Looking at it, it makes NO SENSE how this would "just happen", and the bottom of the car has three, maybe four light surface scratches...this car has never been curbed, or bottomed out!
The brown wire is just hanging out, with a few strands of fresh copper exposed!
- I also have no "fur" around or in the fog light grille!
Does the ECU use this data to help air / fuel mix, or is it ONLY using the IAT (Incoming Air Temperature) sensor in the intake?
Looks like an EASY fix (well, now that I have to FIX the wire harness) as to REPLACE the sensor, you just pull off the inner fender lining.
Dang,
Jake
The brown wire is just hanging out, with a few strands of fresh copper exposed!
- I also have no "fur" around or in the fog light grille!
Does the ECU use this data to help air / fuel mix, or is it ONLY using the IAT (Incoming Air Temperature) sensor in the intake?
Looks like an EASY fix (well, now that I have to FIX the wire harness) as to REPLACE the sensor, you just pull off the inner fender lining.
Dang,
Jake
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Joined: May 2006
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From: Cumberland, RI U.S.A.
2005 C230WZ SS Capri Blue/Ash
My car's temp is always reading a good 5 degrees hotter than what my other car and local bank signs have for outside temp. Dealership replaced the sensor, but it didn't help. I have heard that because the sensor is so close to the ground, and because low to the ground is warmer, that's why the reading is higher.
Cintoman
Cintoman
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From: WNY
2005 w203 C230
Thanks all!,
My wife noted no change in drivability or MPG...So the ambient sensor must not feed the engine ECU.
Here are two pictures, and I am sorry, the disconnected wire (MYSTERY!) did not want to photograph well. The second shot shows what little scuffing there is on the car...no sign of impact, curbing or otherwise.
Thanks,
Jake
My wife noted no change in drivability or MPG...So the ambient sensor must not feed the engine ECU.
Here are two pictures, and I am sorry, the disconnected wire (MYSTERY!) did not want to photograph well. The second shot shows what little scuffing there is on the car...no sign of impact, curbing or otherwise.
Thanks,
Jake
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From: Saint Augustine, FL
1999 CLK320 (sold), 2007 C230 SS (gone), 2000 Grand Marquis, 2011 CR-Z, stay tuned...
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2019 G70 6MT & 2022 Ford Maverick XL
I can't possibly see what ambient light would have to do with the A/C. Did you mean ambient temp? I would have just assumed that's what you meant but given your experience with that dealer, nothing would surprise me. Either way, a bad ambient temp sensor should have no affect on the HVAC.
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From: OC
a quarter mile at a time
My car's temp is always reading a good 5 degrees hotter than what my other car and local bank signs have for outside temp. Dealership replaced the sensor, but it didn't help. I have heard that because the sensor is so close to the ground, and because low to the ground is warmer, that's why the reading is higher.
Cintoman
Cintoman
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Joined: May 2007
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From: Hong Kong/Charlotte
2010 C63
There is an ambient light sensor that adjusts the A/C -- it is meant (I assume) to adjust for sunlight in the cabin, which heats the cabin much faster than just ambient air temperature.
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From: Saint Augustine, FL
1999 CLK320 (sold), 2007 C230 SS (gone), 2000 Grand Marquis, 2011 CR-Z, stay tuned...
I can't possibly see what ambient light would have to do with the A/C. Did you mean ambient temp? I would have just assumed that's what you meant but given your experience with that dealer, nothing would surprise me. Either way, a bad ambient temp sensor should have no affect on the HVAC.
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2019 G70 6MT & 2022 Ford Maverick XL
The "sun sensor" doesn't exist on my 2005 or Drew's 2007 car. I think it's just a placeholder. My car has an ambient light sensor (it adjusts brightness of things during the day, visibly noticeable) but has no affect on the A/C. On pre-facelift cars with digital HVAC controls, though, there was a sun sensor that did adjust A/C.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Only cars fitted with Thermotronic AC have the sun sensor & can put out more cold air on the hot side of the car. Thermatic can't do this.
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From: Saint Augustine, FL
1999 CLK320 (sold), 2007 C230 SS (gone), 2000 Grand Marquis, 2011 CR-Z, stay tuned...
