DodgeIntrepid.Net Forums banner
41 - 60 of 73 Posts

·
Premium Member
Joined
·
292 Posts
Discussion Starter · #41 · (Edited)
I ran the ATC diagnostics and got these two codes: ATC Ambient Temp Sensor Failure (DTC 25) and Evaporator Sensor Failure (DTC 35). I just replaced the ambient sensor this summer. He had to have unplugged the evaporator temp sensor to see inside. Maybe he did break it. Or it was already broken. I couldn't prove anything. I don't know what lead him to look at it. Maybe he knew how to retrieve the codes. He didn't say anything about the DTC 25.

The engine temperature shot up shortly after the compressor stopped. My instinct leads me to believe a high speed fan problem. But now the AC will never work unless the evaporator sensor is replaced. Is this something I could without taking the dash apart? I'm trying to search the service manual, but not finding what I need.

I found these instructions:

Removal
Disconnect negative battery cable. Remove right underpanel silencer. Remove evaporator temperature sensor
(evaporator probe) connector. Twist evaporator probe access plate 1/4 turn counterclockwise, and remove plate.
Plate is located at center of A/C-heater housing. Remove evaporator temperature sensor probe. Mark old hole.

Installation
There are 3 holes manufactured for evaporator probe insertion. Install new evaporator temperature sensor in
uppermost new hole. DO NOT install in old hole(s). To complete installation, reverse removal procedure.

Font Map Auto part Parallel Line art
 

·
Premium Member
Joined
·
17,892 Posts

·
Premium Member
Joined
·
17,892 Posts
No prob.

Maybe that didn't come up on an ebay search for you because you included "Chrysler" with the part number (they use "MOPAR" on the auction page)? Who knew! I found it using an internet search engine searching on "Chrysler" and the part number - otherwise, as I said, that same search on ebay didn't see it.
 

·
Premium Member
Joined
·
292 Posts
Discussion Starter · #46 ·
I crawled up under the dash to find the sensor. I was able to turn the small door, but it wouldn't pull out. It would only fall into the opening. I turned it quite a bit with no luck. Maybe once I have the new part, it will give me more of a clue as to how the door is removed.

I'm not sure how the plug disconnects from the door. Maybe the metal clip has to be popped off? I didn't want to mess with it too much until the new part is here Thursday. There's very little room to work.

I have to drop the car off tomorrow for the overheating problem. I can show the shop owner the picture and let him explain why the dash needs to come out.

At least I know how another part of the car is supposed to work.

Hood Automotive lighting Motor vehicle Steering part Automotive design
 

·
Premium Member
Joined
·
292 Posts
Discussion Starter · #47 ·
The new probe arrived today. I talked to the shop owner about replacing it. He had also tried to open the door by turning it, but it would just keep turning and fall inward. I think he thought the probe, like a lot of cars, was made of plastic and had broken off in the evaporator. Friday, he's going to take another crack at replacing it. I told him to cut the old door out, break it or whatever to get it out. Maybe he can analyze the new probe to get an idea how to get it out. I would try it, but I'm too old.

The Concorde's probe is made of metal.

Kitchen utensil Cutlery Font Cable Fashion accessory


Table Personal protective equipment Fashion accessory Metal Audio equipment
 

·
Premium Member
Joined
·
292 Posts
Discussion Starter · #48 ·
I reread the instructions and step 5 indicates the plate must be pushed inside the A/C unit and orientated in such a way that the plate can be removed. So it's behaving as it should.
Font Parallel Paper Art Line art
 

·
Registered
Joined
·
4,393 Posts
The evap Temp sensor is a PITA to do. Make sure you do not re use the same hole. HAS to be a new hole made through the fins. Also, there is a chance the old one may not come out. Mine would not. So I cut the wires and left it in there.

IIRC I did have to twist while prying, and turn it sideways to get it out.
 

·
Premium Member
Joined
·
292 Posts
Discussion Starter · #53 ·
I ran a few errands this morning. The outside air temperature was in the upper 70's. I had the ATC on auto and the AC worked. I was watching the engine temp, because I've become a bit paranoid about it. After driving 3 or 4 miles and stopping at several lights, the engine temp was 195. It stayed there for a few more mile and then went up to 197 and then 198. I would have thought it would be fully warmed up after driving 3 or 4 miles in traffic. It was sunny and warm.

I stopped off at a place. Following that the engine temp stayed in the upper 190's. When I stopped at a light, it went up to 206 and stayed there, until I started moving again. It then dropped back to the upper 190's. Occasionally it hit 200.

I went out again this evening. OTIS showed 81 degrees. Car mostly kept around 197 for must of the trip. After driving a bit, I stopped and was idling in a parking lot for about 10 minutes. Engine temp dropped to 191 and stayed there, until I began driving again. Waiting at one light, it got up to 206 and back to 197 when driving. Another light, it got up to 209 while waiting, before dropping to the upper 190's when I got going again.

Normally, it would stay right around 200, plus or minus a couple of degrees. That was before the Evaporator sensor failed. Are the temperatures I reported OK? It's still seems somewhat off to me. It seems to run on the cool side, until I stop at a light.
 

·
Premium Member
Joined
·
17,892 Posts
At the beginning of this thread, we discussed that.
Yep.

Besides replacing the evap. sensor, do you know what they did to stop the overheating problem? Radiator fans seem to be working right - off, low speed, high speed?

IIRC, that thermostat proved itself to be working correctly before your fans went out, causing it to overheat. Just wondering if they're working right. Also, i believe the ambient temperature is cooler now, so if your new thermostat tends to run towards more open, it might regulate OK in the warmer weather where the fans would be doing most if the regulating, but in cooler weather, it would rely on the modulation of the thermostat to regulate the temperature, in which case you could try another dealer one. Hard to say - I'm just suggesting possibilities. So my two suggestions are that the fans may be on more than they should be or the thermostat calibration may be slightly off.

You seem to think it's running to the cooler side based on your temp. measurements. What is your gauge showing? Typical steady state is with gauge showing slightly below halfway. The engine temp. readings you're getting are from a DRB?
 

·
Premium Member
Joined
·
292 Posts
Discussion Starter · #57 · (Edited)
Product Gadget Font Material property Magenta


I'm using one of these. » ScanGauge II I have it set to display the water temperature. I've been using it for the past 9 years. I keep it perched on the steering column, just under the cluster for easy reading. Looking at the temp gauge in the cluster, it would be difficult to notice much of a change. When the shop test drove it after replacing the evaporator sensor, the ScanGauge was unplugged from the ODBII port, so I'm sure he probably watched the gauge in the cluster.

Up until the evaporator sensor went out this last time, the system was working as it normally would. The shop had previously replaced the fan assembly and all seemed good. The water temp stayed right around 200.

I read a generic article on how the ECU controls the fans. It sounds complicated.

I checked the antifreeze level in the overflow tank and it was down a couple of inches from the cold fill level. I remember that it was down like when I started the thread. I added more back then and did so now. The oil looks good. It's not milky. I don't know if a few inches of antifreeze in the overflow tank would make that much difference in cooling.
 

·
Premium Member
Joined
·
292 Posts
Discussion Starter · #58 · (Edited)
Took the car on 10 - 12 mile trip. Moderate traffic and lots of traffic lights. The outside air temp was in the low 70's and cloudy. The OTIS temp showed 77 - 78. I had the ATC set to 73.

I stopped off about 2/3's of the way. While in the parking lot, I let it idle for about 5 minutes. Engine temp stayed at 195. I went and opened the hood, while it was running. The AC compressor ran almost all of time I watched it, as did the high speed fan. A couple of times, the compressor clutch would disengage for about 2 seconds, as did the high speed fan turn off.

When I got home, I again let the car idle for about 10 minutes, with the ATC set to 73. I watched the compressor and it ran the entire time. It never cycled off and the high speed fan ran the entire time.

I don't know if this is normal behavior for the compressor to run almost all the time. I would have thought it would cycle on and off. It's not like it had to work hard to cool the car's interior. The ATC fans speed stayed on low. And since the compressor runs almost all the time, so does the high speed fan. Obviously, I don't know what the compressor is doing, while I'm driving. The AC seems to work. The highest temp it's gotten up to outside, since the evaporator sensor was replaced, was 82 and sunny.

I always like to know how things work. At the shop, when I give insight into what I have learned, they sort of make fun of me. They're the experts, I'm not. Sort of like stepping on their toes. I know they have years of experience behind them, I don't. They told me I graduated from the YouTube School of Mechanics. They wanted to take the dash apart, because he thought the sensor was made of plastic, old and broken off inside, probably like many other cars they worked on. I learned that it wasn't necessary. I just want to make sure I know what I'm talking about, before I say something to them.

They did check the system for a proper charge, when they told me the sensor was not working.
 

·
Registered
Joined
·
70 Posts
At the shop, when I give incite into what I have learned, they sort of make fun of me
Sounds like the shop owners/employees should learn some courtesy, especially when you're giving them BIG bucks to keep your car on the road.

And since the compressor runs almost all the time, so does the high speed fan
I remember on my car I had to change out the AC transducer switch as my cooling fans started running on high all the time.
 

·
Premium Member
Joined
·
292 Posts
Discussion Starter · #60 ·
I ran some more tests. It's only about 62 outside. I just backed the car out of the garage and let it idle. I set the ATC to 84. The compressor ran 99% of the time. It did stop a couple of times for about 5 seconds. The metal tube coming out of the compressor, I'm guessing the high pressure side, was very cold. To the point where water was condensing on it and dripping off. I've seen condensation on it, but never dripping off.

I switched the AC to 70 and the air temp at the vents was extremely cold. At 84, the heat was anemic. I have a feeling that the evaporator sensor is not shutting down the compressor. In the ATC diagnostic mode, there are no codes.
 
41 - 60 of 73 Posts
Top