1997 850 GLT ECC possible problem?

Post by **m491** » 16 Dec 2014, 18:02

My son's 850 GLT has had a heating issue last week. The car was blowing very warm heat and the when restarted it didn't blow any heat until I played with the team control knobs and then it started to blow hot again.

Another time I started the car to let it warm up on a cold morning and the ECC lights were flashing for about 30 seconds. The lights stopped flashing and the heat was blowing hot. The time after that the same issue, 30 seconds of flashing lights and good heat.

My question, is the ECC going bad at this point? Would the Volvo dealer be my next step to see if the ECC is showing error codes?

Is have been looking for anyone who rebuilds the ECC units. Are there any businesses out thee offering rebuilds like the antilock system.

Post by **misha** » 16 Dec 2014, 18:40

I would say that few drops of oil onto a blower motor shaft will cure the problem or motor brushes need replacement.

Does it squeal?

Redneck · Post by **Redneck** » 16 Dec 2014, 19:24

There are ways to read ECC error codes yourself. Search this forum how to build a simple device to do that. However, in my experience many of the error codes that get stored are wrong. Before you do anything else, make sure that the blower motor spins. Remove the cabin filter and look at the motor to see if it spins when the fan is on, if not. Take it out and either lubricate it or buy a new motor insert. I exchanged my blower motor. Sometimes the ECC error codes just go away on their own after you disconnect and reconnect all cables including the resistor.

In your case either the motor does not spin, or the flap that channels air through the heater core is stuck closed.

Volvo dealer will charge you through the nose for fixing this:)

Post by **m491** » 16 Dec 2014, 19:26

No squealing. The flaps not opening might be an option. The flashing lights are the part that makes me think I have an ECC issue.

Redneck · Post by **Redneck** » 16 Dec 2014, 19:29

ECC is most likely fine.

Post by **Ben850** » 16 Dec 2014, 22:27

m491 wrote:No squealing. The flaps not opening might be an option. The flashing lights are the part that makes me think I have an ECC issue.

The flashing lights are letting you know that a code has been set and needs to be read and cleared.

The codes need to be addressed and fixed. Check and clear codes again if needed.

I made an OBD I style flash code reader that can do that. I will add the thread when I find it again.

Or you can search the repair database. I believe Matthew added it there. Also in the tools forum.

Post by **jreed** » 17 Dec 2014, 05:12

I had great results building a little code reader for the ECC and using it to read the errors it had encountered. I agree with the above poster that it generally helpful to use the code reader to erase the codes, and then see which codes return right away... those codes are more likely to indicate current problems in the system.

You can make a code reader for small money using the circuit diagram here:
https://www.matthewsvolvosite.com/forums ... 43#p251189

I wrote up and posted one example of using the code reader to identify a failed component and then fixing the component:
https://www.matthewsvolvosite.com/forums ... =1&t=50525

Good luck! Let us know how it goes and how we can help out!

Post by **abscate** » 18 Dec 2014, 04:52

"ECC" is used to both describe the climate unit (electronic vs manual climate control or MCC) and the dashboard control unit for the electronic system.

This can cause confusion.