98 V70XC AC High Pressure Fitting Location?

[StoningtonXC70]

I just did as quick AC recharge on my 98 V70XC which is now making ice cold air, better than it ever worked in the 5 years I've had the car. One thing I was not able to locate however, was the high side fitting. Lacking access to it, I just filled using the low side gauge. I would like to do a high side and low side pressure check to get a set of baseline readings for future reference to keep an eye on the system in case the dreaded evaporator leak shows up. I believe I have dodged that bullet so far, as the pressure in the system prior to the recharge was not too low below normal.

Prior to this posting, I did a search on this subject and the available info seems only to apply to the 2002 and later models.

[JRL]

You can't
No high pressure port on these cars, you did what we all do.
These cars take exactly 1.65 lbs (approx 26 oz) of R134 or 2 oz over two complete cans.
If I have a car that's totally out I use 2 cans and it's just fine.

[StoningtonXC70]

After reading up on AC in a Chilton's auto AC and heating manual, I can see why Volvo did not put a high pressure port on the 98 V70 system - normal high side pressure on these cars is listed at over 500PSI- over twice what most other systems use! What is so different about the V70 system for 98 time frame?

[bob]

There is one way to read the high side. Requires a scan tool. The AC high side pressure is reported to the ECM for cooling fan control.

[JRL]

You have A/C, I would not worry about it right now

[StoningtonXC70]

Yep - been working great, especially after I put in a replacement blower - the original one had its brushes worn down to a nub.

FWIW, I will pass a long a bizarre intermittent problem I had with the AC clutch sometimes not engaging on a random basis in my 94 Escort - turned out to be an intermittent high resistance in the wire between the clutch itself on the +12V supply side and the clutch control relays. Not the connectors at either end of the wire, but somewhere in the approximate 6 foot run of the wire itself in its harness. When it failed, it was reading about 50 ohms end to end. Since the clutch resistance is only about 4 ohms, less than 1/10 of the normal +12 volts was making it to the clutch in the failed condition! Spliced in new wiring on both the supply and ground return sides of the clutch harness and now all better....wonder how many new (expensive) parts and associated labor costs the system would have if I had a dealership try to find this problem?

[StoningtonXC70]

BTW, I am still getting about twenty second or so of flashing AC LEDS on engine start even though everything appears to be working well. Are some old failure codes locked in that must be read and cleared? Can that be done without a scan tool?

[JRL]

You can't clear it, it will come right back. Eventually... the lights won't stop flashing and your AC stop working. As long as they're flashing, no workee!
It's either your cabin temp (dash) sensor or a failing blower motor or resistor pack.
The only way to get a defintive answer as to which one it is is to have the internal codes read at Volvo with their scanner, a generic scanner will not help you with this.

I will not get into the discussion again how to clean/blow the dirt out of the sensor but that is your first step, do a search on it.
(I got into an argument here a month ago for no good reason on how to clean it, so you're going to have to have someone else explain it to you, I'm sorry).

[StoningtonXC70]

Well, now the lights don't flash anymore. Go figure!

Correction....if I start the car with the AC in the normal AC mode, the lights don't flash. If I have the recirculate mode selected at start, they will flash for about 20 seconds. I vaguely recall reading somewhere that this is normal, Volvo doesn't want you to use recirc for extended periods.Everything otherwise fine. I had to shut the vent to the left of the dash today to keep my hand on the steering wheel from freezing up!