'98 V70 EEC Issues Topic is solved

[TrishP]

Greetings All:
It's been awhile
I believe my girl needs some freon,as there is no cold air, and I can hear an intermittent clicking sound.
Just haven't been able to get her to a garage.
But, the other issue is that the entire EEC unit become non-responsive ;( with orange blinking indicators.
I checked the fuses and replaced the cabin filter, but it was still flat lining.
Then, I generously sprayed the thermister with canned air & voila, the fan is blowing stronger than ever and the lights are off.
Which brings me to my question: Do the CODES need to be reset, and, if so, how?
Thanks!

[abscate]

You need to read them off and see what they are telling you. You have numbers on your temperature dials right?

It’s normal for the compressor to cycle on these cars at normal summer temperatures

[misha]

On ECC...if there are no blinking ac/rec lights on every startup,there are no stored codes and if there was any ...they clear themselves automatically once the problem is solved.

Thermistor itself(if you are talking about cabin temperature sensor on the dash)if it's bad it will not prevent blower fan from working...so something else is going on there.

ECC on s,v,c,xc70 is fully obdII and you can read the codes with VOL-FCR.
Generic code readers can't read anything else but engine dtc.

[scot850]

Normally I am 100% with our friend Misha. However, this time I disagree somewhat. If the cabin sensor is clogged (and I have seen them jammed solid with hair and other stuff I probably don't want to know) That jams the little fan around the sensor that draws the cabin air over it. If the fan can't turn and draw the air over the thermocouple the junk also insulates the sensor. When that happens it sends a signal to the ECC and stops it.

I had this exact issue on a 98 V70XC. I got the code for failed sensor with Vol-FCR. Removing the sensor (fairly easy but fiddly) is not too hard and it is worth cleaning the sensor properly. I use acetone and cotton buds as well as a small artists brush.

If you found all things started after blowing the sensor clear then this vindicates my experience.

I believe I wrote a how-to a few years back on cabin sensor cleaning.

Neil.

[misha]

You could be right Neil...and maybe it's something with 70 series because they have just one cabin temp.sensor where 850 have two of them behind grab handle on the roof on driver's and passenger's side.

I had a seized passenger side cabin temp sensor(behind handle on the roof)on my '97 850 with ECC and it didn't prevent blower fan from working.
Ac/rec lights were blinking on every startup but blower fan(heater blower) worked normally.

So i speak from my own experience.

Only thing that can prevent the blower fan from working is the blower motor which is pulling too much current and ecc turns it off by default to protect the power stage...and bad power stage itself.

Working principle of ECC on 850 & s,v,c,xc70 are exactly the same...except that 850 have two cabin temp.sensor where 70 series have only one.

ECC units use cabin temp sensor/s to reach and maintain selected temperature in the cabin when settings are on AUT.
Otherwise....when you manually turn the slider to a desired fan speed and turn the knob for any other direction out of AUT...cabin temp.sensor is out of use.

[abscate]

Do you guys have the cool auto recirculate features in the 850 or did you miss that party?

We can set ours up to recirculate for a set period then go back to fresh.

Apparently , pushing a button is beyond our NA market

[misha]

On 850...and it should be the same on 70 series with ECC....when you put middle knob and slider to AUT...ECC decides about position of REC damper motor for the best cooling or heating results.

You can always set it manually to fully closed or fully open by hitting the REC button,just like you can operate a slider manually for desired blower speed or direction.

[TrishP]

Addendum: She's baaaack ;(
So, the canned air on the thermister seemed to remedy the EEC blinking lights. They no longer blink.
And, the fan worked, albeit briefly.
Now, the fan turns on strong when I start the car and slowly fades out in a few minutes.
Curiously, when it IS running, it goes faster if I rev the engine---lol.
A similar situation occurred last year with the fan and the culprit was the cabin filter.
This is an aside, but we found evidence that a mouse or squirrel had been in the engine compartment (seed hulls on top of engine and under the air filter)!
The other vexing issue is the car was stalling at stops last two times it was driven.
Due to the pandemic, it hasn't been used as much as usual. I read that this can be an issue with the MAF. Can anything be determined by a visual inspection in this regard?
The car has no rust and 130K. I love driving it and hope to keep it going. But our mechanic retired a few years ago, so we are currently DIY on a budget and this site is so very appreciated!

[abscate]

I’m doing house calls in Western CT, Trish. Have a decent scanner which can read both engine amd ECC control unit codes.

It sounds like your blower motor is giving up, lubing it might help. You can also buy a TYC unit for about $100

Not a horrible R/R. About one hour

[TrishP]

Greetings:
Sorry for delayed reply--l.i.f.e.

We are going to attempt the blower motor lube to see if it remedies the problem.
Can you suggest what type to use?
If that doesn't work will try the replacement. We don't live far from FCP.

My husband actually got an ODBII reader a week ago. It's not a high end model; but, I took the car out for a longer spin today and checked the read after that. So, please forgive my neophyte form: the live data on the MAF was that when I revved the engine it went from 3ish to 15. Should I assume that it's still operating OK?
Almost home, I noticed a bit of "tugging" on inclines.
The "pending" and only code that appeared was PO410.
Need help on this one!