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Discussion Starter · #1 · (Edited)
Folks...after waiting over an hour for Air Force One to depart the airport I was able to get my bags and head to the R (2005 V70R / 68k miles / manual / original owner) and when I proceeded to pay for parking I noticed my A/C would get hot when I wasn't moving...okay, I knew the fan was inop at this point. After arriving home and restarting it, the engine system message appeared.

Now the car won't start correctly and I get ABS lights, Engine Service light and the chassis service message.

Any thoughts??????
 

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There isn't a fan switch, it is a temp sensor and the ECM reads coolant temp and a/c high pressure and decides what fan speed level to use. When you jumped sensor you set an engine coolant temp (ECT) sensor if that is what you jumped or the fuel pressure sensor code if that was it. ECT sensor is next to radiator hose and the FPS is on end of aluminum fuel manifold.
Your problem is much more likely to be a/c pressure sensor as the engine temp getting high enough to trigger fan takes 10-12 minutes from start unless it is 90+ F then it is still 8-10 minutes. The fan will be operated for a/c pressure reasons within 30 seconds if the outside temp is over 80F.
The Car needs to be scanned with a scanner that can read parameters from ECM so the high side pressure sensor can be checked for plausibility.
The high side sensor on P2's is on the receiver/drier and requires bumpper be removed and the system recovered of refrigerant in order to change it. The sensor is not on a schraeder valve sealed port as on many of the Volvo models.
 

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Discussion Starter · #4 ·
Thanks!

At the dealer...tech scanned it. Says dozens of codes. Car isn't seeing the temp sensor...not seeing boost or fuel pressure. Going to replace the temp sensor now and rescan. Fingers crossed. $75 an hour...ugh.

Asked him about the a/c sensor. He said not likely BUT what you indicate about the a/c makes perfect sense. It was 85 degrees and I noticed the a/c only cooled whe. Car was moving due to no fan.

I'm kinda at his mercy....
 

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One of the sensors can fail and kill Vref (supply voltage to sensors that gets modded to be the return signal to ECM) and make several not read. Or a wire shorted on Vref feed to one of the sensors.
 

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Discussion Starter · #6 ·
Thanks again

He's trying to track it down...hard ECM reset, updated the software, tried a new temp sensor (no change). He's now cleaning up all the 'contacts' and grounds.
 

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He should load a group of the sensors that have had codes on the VIDA parameter list screen and then hit "ENLARGE" so thney are easy to see from the car when he unplugs sensors one at a time and waits for the screen to refresh (5 seconds or so) and then see if the reading for the remaining sensors become normal again. The one unplugged when the readings normalize is the bad guy. If no bad guy is found then the circuit at the easy accessible connector should be probed to see if Vref (Volvo just refers to it a signal supply voltage in the signal spec charts) is at 5V +/- 0.10 V.
The bad part is the a/c pressure sensor is a bugger to get to to un plug. The a/c pressure sensor has a small history of causing this type problem.

Which dealer?
 

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Discussion Starter · #8 ·
Third Thanks!

McLaughlin Volvo in Moline, IL - the service writer (Beth) has been super nice to work with and I know the tech is pulling his hair out on this one.

Thank you for taking your time to reply so quickly. I'll call them and see if what you suggest can be done.

Many thanks.

Brian
 

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Discussion Starter · #9 ·
Update

Beth called...tech thinks it's a bad ECM.... THANK GOODNESS for Swedespeed or I won't have realized the $1,300 part is still under warranty!
 
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