SL/R129: BeckwithR
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BeckwithR
I have a 94 SL600 V12. The air blows cold/cool and not hot, although I have the temperature gauge turned as high as it will go. Any help with this would be appreciated. Is this something common for this model?
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From: Northwich
R230 350SL
Well clearly that isn’t the way it should be. However you’re best route is to put a code reader on it and see if the car is storing any faults that can lead you to the cause. Without that approach you’re just going to be guessing as there could be several things giving that symptom.
Broadly speaking there here are two lines to follow. The heating can’t deliver if the engine isnt getting up to temperature. The normal reason for these circumstances would be a thermostat that is stuck in the open position. What does your temp gauge do, does it read low, or fluctuate during normal driving, or lower during higher speed runs? All of these could point to a stuck thermostat.
Alternatively if the engine is running at correct temperature, then the problem must lie with the climate control system. There are so many areas in this that could cause your problem that I don’t think you’ll ever pin it down without starting by reading codes.
Get the codes read.
Broadly speaking there here are two lines to follow. The heating can’t deliver if the engine isnt getting up to temperature. The normal reason for these circumstances would be a thermostat that is stuck in the open position. What does your temp gauge do, does it read low, or fluctuate during normal driving, or lower during higher speed runs? All of these could point to a stuck thermostat.
Alternatively if the engine is running at correct temperature, then the problem must lie with the climate control system. There are so many areas in this that could cause your problem that I don’t think you’ll ever pin it down without starting by reading codes.
Get the codes read.
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Thanks, I thought it could be the thermostat I didn't want to just start fishing. Your suggestion is a good one and I will do that. Thanks again. Because you mentioned the temp gauge I am thinking it could be the climate control, because the temp stays constant.
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E55, GLS450, GL63, GLE350
In addition, posting in the correct forum tends to yield better results. Post here. https://mbworld.org/forums/sl-class-r129-18/
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'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
No code reader can communicate with the climate control of a '94 SL. However, comprehensive diagnostics can be obtained directly from the controller itself. See here: http://manual.startekinfo.com/manual/JSP/cc/3_1/m11.jsp. My focus would be on looking at the various sensor readings for an implausible value.
Thread Starter
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Joined: Jun 2016
Posts: 87
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W140 & W220
No code reader can communicate with the climate control of a '94 SL. However, comprehensive diagnostics can be obtained directly from the controller itself. See here: http://manual.startekinfo.com/manual/JSP/cc/3_1/m11.jsp. My focus would be on looking at the various sensor readings for an implausible value.
The directions to use the process that allows you to display the DTC's, shows a button with an f on it. There is no button with this letter on my dash. It says to press the f button, the button with rest on it and the button that indicates airflow throughout the car at the same time to produce the DTC's.
