A/C flashing leds in switches

Pepitoracing · Post by **Pepitoracing** » 16 May 2008, 12:38

I have a 97 850GLT. I have swapped out the ECC twice, changed the Heater core, and recharged the system. I still can't get the ECC to throw the air in any other direction than the fron t vents. I also can't get the passenger side to change the temp either. It will only blow cold - super cold - 40 degrees. I do have blinking lights on the ECC but haven't the slighest clue how to read them. Can anyone please help me. Thanks!

Post by **Ozark Lee** » 16 May 2008, 14:11

In order to read the codes from the system on a '97 it takes a Volvo specific scan tool. The dealer can do it, most independent shops that do a lot of Volvo work can read them, and VOL-FCR software along with their special cable and a laptop will read them.

Based on your description of the problems I would say that you have either bad motors or broken shafts on your air mode damper and your passenger's side temperature damper motor.

The motors are on the passenger's side of the climate unit. You need to remove the glove box and the lower dash panel to get to them.

...Lee

Pepitoracing · Post by **Pepitoracing** » 17 May 2008, 08:56

Thanks for the help! The volvo dealership wont tell me the codes. They only told me that it would run about $300 for them to do a "diagnostic run" on the car. I am not prepared to spend $300 for them to just tell me what's wrong. The car runs great! Summer is right around the corner and we get a lot of rain and the windows will keep fogging up. Is there another way to get the codes? I read about the "blinking LED method" but I don't know exactly what to look for. The REC and A/C LED blink alot on the car everytime I start the car. I apologize for my naiveness but when it comes to Volvos I am pretty ignorant. I was brought up on Chevys. I like my Volvo though! I want to keep it but I need the A/C to work properly. Thanks for the feedback and advise!

Post by **MadeInJapan** » 17 May 2008, 10:55

Go to another dealer....ask them to put the money you have to spend for diagnostics towards the repair if you choose to use them for the repair. Other than that, some indy shops might have the tools to read the A/C code. Good luck!

Post by **Ozark Lee** » 17 May 2008, 13:18

Dealerships are obscene. They give an otherwise great car a really bad reputation.

Pull the motors off of the sides if the climate control unit and observe their movement as you operate the air mode controls and temperature controls. A bad motor is usually obvious to the eye. Also inspect the square drive shafts on the dampers. They can split and not move the dampers along with the motors.

There is no way to decipher the flashing Rec and A/C lights. That is simply a warning that the system is in an error state.

...Lee

jtphelps · Post by **jtphelps** » 10 May 2009, 15:00

I recently bought a 98 Volvo V70 GLT with 170k miles. It needed quite a bit of TLC due to the previous owners neglect and one problem was finding the fault in the ECC. Thanks to this site I tried the cabin air sensor FIRST! I removed the part quickly, cleaned it with compressed air, a Q Tip and electronic parts cleaner. Reassembly was fast and the lights are back to normal.

Great TIP guys. Thanks so much! I've seen so many darn lights on this car since I got it and this was the last one I had to tackle. It was the easiest and cheapest thus far and I feel like I am now behind a beautiful machine!

Post by **kelvin6** » 11 May 2009, 00:02

Sometimes it could be the ECC itself. What doesn't surprise me is that the electronics inside can easily fail. I noticed on my ECCU panel that the panel is usually pretty warm compared to the other dash stuff. Leading me to believe that the electronics are being heated up either by themselves or by the illumination lamps. Heat destroys electrical components, especially capacitors.

I've been getting the flashing LEDs for a while and even though i've been clearing and checking the codes with Vol-FCR, it just keeps returning. Every time it flashes, the code I keep getting pertains to the passenger side temp sensor faulty. Sure enough I replaced that sensor, THREE times and it still does it. I've checked the connector and the harness and found no damage, so my suspicion is on the ECC board itself.

A interesting note about heat and electronics. In newer electronics and probably in newer cars, some electronic boards and components are soldered with lead-free solder to be part of the RoHS compliance (lead-free), and because IC chips are running faster and smaller, they can produce enough heat to almost desolder itself. This was seen on the Microsoft Xbox where one of the ICs generated so much heat it was destroying the solder joint (almost desoldering itself!). This could in theory happen to new car electronics which could be RoHS compliant... so don't be surprised if the electronics today don't last as long as they should.