EC light on - display stuck on LO - buttons unresponsive
#1
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99 W210 E320
EC light on - display stuck on LO - buttons unresponsive
Hello all, first let me say this is a very informative site, thanks to all. I've read through allot of the AC problems and it is some very good information. I've tried all of them but my problem is a little different. I just bought the car and the guy said "it's just low on refrigerant" etc. I was leary but my wife loved the car. Anyway, my brother hooked up his machine, took out 8oz and tried to put in 2lbs - got up to 1lb and stopped. He was finally able to get 2lbs of refrigarent (+oil) into the lower connection (he has a machine that does this, he's been a mechanic for about 40 years now). There's no leaks in the system (used machine to test for leaks) so I know it's no longer low on refrigerant but here's where it's different:
1. Automatice climate control says Off
2. Turn on fan - automatic climate control turns on and says LO on both sides.
3. Auto button is lit on driver side
4. EC button is lit
5. Activated charcoal filter is lit
The only buttons that work in the ACC unit is the rear defrost button (turns on and off when I press it) and the fan (can go higher, lower, shut off, etc.) None of the other buttons work - cannot turn off EC, cannot turn of charcoal filter, cannot change temperature, etc.
I can hold down the REST button for 5 to 10 seconds to get to the diagnostics - but I can only see the first sensor, I cannot cycle through the rest of the sensors - hitting Auto or any other button for that matter will not make the display move. The first sensor reading is around 49 to 51 -sometimes it jumps back and fourth so to me the car thinks it's already cold outside when in fact it's like 90 in the car.
We've hooked up the diag machine underneath the dash and cleared 1 code - for a missing bulb in the back - P1747 if I remember correctly, the parts on order so that will be taken care but no other codes appear. From reading the forums this can also be cleared from the automatic climate control unit but I can't cycle through the data.
Fuses have been checked at all 3 locations and they are all good.
The compressor turns so it's not locked - with the EC button lit it will never engage from my understanding.
Any ideas as to why I can't change any of the settings or what might be wrong with the automatic climate control unit? I've read allot on the forums and even videos on youtube and they are all great except I cannot get the car to show me that info - the buttons don't seem to respond except for the select few.
1. Automatice climate control says Off
2. Turn on fan - automatic climate control turns on and says LO on both sides.
3. Auto button is lit on driver side
4. EC button is lit
5. Activated charcoal filter is lit
The only buttons that work in the ACC unit is the rear defrost button (turns on and off when I press it) and the fan (can go higher, lower, shut off, etc.) None of the other buttons work - cannot turn off EC, cannot turn of charcoal filter, cannot change temperature, etc.
I can hold down the REST button for 5 to 10 seconds to get to the diagnostics - but I can only see the first sensor, I cannot cycle through the rest of the sensors - hitting Auto or any other button for that matter will not make the display move. The first sensor reading is around 49 to 51 -sometimes it jumps back and fourth so to me the car thinks it's already cold outside when in fact it's like 90 in the car.
We've hooked up the diag machine underneath the dash and cleared 1 code - for a missing bulb in the back - P1747 if I remember correctly, the parts on order so that will be taken care but no other codes appear. From reading the forums this can also be cleared from the automatic climate control unit but I can't cycle through the data.
Fuses have been checked at all 3 locations and they are all good.
The compressor turns so it's not locked - with the EC button lit it will never engage from my understanding.
Any ideas as to why I can't change any of the settings or what might be wrong with the automatic climate control unit? I've read allot on the forums and even videos on youtube and they are all great except I cannot get the car to show me that info - the buttons don't seem to respond except for the select few.
#2
Out Of Control!!
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Well if what you say is correctly reported------you have a very bad AC control unit, they can't be repaired and a used one has to be coded to your car by factory software.
If the car was mine I would go back to the babushka that sold you the car and ask for my money back!!
PS: If you can't clear the faults via the AC control unit or by factory software you will NEVER turn the EC lamp off and therefore the compressor will NEVER turn on.
If the car was mine I would go back to the babushka that sold you the car and ask for my money back!!
PS: If you can't clear the faults via the AC control unit or by factory software you will NEVER turn the EC lamp off and therefore the compressor will NEVER turn on.
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99 W210 E320
My wife is taking the car to the dealer today. They are charging $54 to run diagnostics on it. Will report back with what they find. I have a feeling the AC control unit is bad. I noticed that while test driving it last night all of the lights on the console where lit except the AC control unit. We have contacted the seller so he is aware of what's going on and he actually called today to see if the car still has problems so I give the guy credit for keeping in contact after selling the vehicle.
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99 W210 E320
Hello Plutoe, you were right on the money - bad AC control unit. They ran diagnotics on the entire car, the only other problem is a bad SRS sensor on the passanger side front seat. Parts and labor to replace SRS sensor is $486 but he said it's not necessary at this time.
The cost to replace the AC control unit? $488 for the new one and $130 for labor so $618 out the door. That's allot less then I thought it was going to be - even the mechanic was suprrised at the price of the unit, he thought it was going to be allot more. He said that on the 99 model the module is plug and play, no need to reprogram. We'll see what happens when they replace it.
The cost to replace the AC control unit? $488 for the new one and $130 for labor so $618 out the door. That's allot less then I thought it was going to be - even the mechanic was suprrised at the price of the unit, he thought it was going to be allot more. He said that on the 99 model the module is plug and play, no need to reprogram. We'll see what happens when they replace it.