2009 S80 3.2 133,000 mileage
1st problem) I've been ignoring the "Check Engine"light for a few weeks.
Finally had my mechanic use his OBD sensor to check code issues(SMOG this year coming up fast, mid July!)....Came back that the ECM wasn't not working and throwing other codes(ie, Transmission, has a stumble in 2-3shift). Decided to pickup a used s80 ECM with same number as mine from a low mileage wreck (will test that approach this next week with updated software reprograming).
Disconnected battery to reset Check Engine light today(yes it went off...YouTube tip), ran it down the road a short distance to warm up the Cat B4 trying to pass emissions.....
DIDN'T WORK! Came back: {OBDII Not Ready}...couldn't test: Cat and Evap System
Soooo, test guy said to try the "Drive Cycle" and come back after that and maybe 200 miles more regular driving.
Any suggestions in addition to the above??...
Plan B is to install ECU and start over....
I've had Volvo's for 35yrs and they've all given me over 250,000++ miles...1985 745 Turbo Diesel and 1995 745 Turbo....
If it gets too crazy, I'll look for a 2008-20015 S80 with low mileage so I can transfer over my upgraded suspension/tires/headlights and donate the bones to a worthy cause...
Any suggestions greatly appreciated.

DQ....
Always Jousting at Windmills (hoping this isn't one of them)

 

Codes get stored regardless of the light. Go over to autozone, borrow a code reader and clear the codes. Next google for the recommended drive cycle procedure. What happens is some of the fault codes are averaging codes that measure conditions over time. The driving cycle varies road speed etc to give the ECU enough data points to set the "ready" flag in the shortest amount of time. Otherwise you can simply drive around mixing city/highway and expect it to resolve by 200 miles. If during the drive cycle a code resets, the light will return and you'll be seeing your tech again.

PS - its also pretty rare for ECUs to fail. More often there may be sensor issues or connectivity issues to other computers. A good first step would be to have your tech remove and clean all the connectors then reinstall and clear all codes. I've had to do this with the TCU on my S40 and that fixed the odd shifting issues we were having.

 

You say you have an EVAP code, these are pesky to get rid of, and anytime you clear your code you have to wait until it runs all the tests. Figure at least 100 miles unless you follow the recommended course, which can be difficult.
BUT, regardless, the EVAP test will only run if your tank is between 1/4 and 3/4 full. Too much or too little gas in the tank and it won't run no matter how long you drive.

Finally, is your mechanic an actual VOLVO mechanic (independent or dealer)? Making a diagnosis of a computer fault like an ECM off just an OBD reader is sketchy, at best.
Volvo uses a propietary program called VIDA.I know of no reader that most general mechanics have that will interface with Volvo's 'puter. The OBD readers pretty much just check if the systen is ready and a limited number of sensors report that they are good.

I would reconsider my choice of mechanics if it was my car.

 

My mechanic uses a VIDA, it threw 2 1/2 pages of codes!! He erased them all and I've been driving the past few days to cycle through properly. Over 200 miles and no Check Engine Light...yet! However, today I'll try for the proper full Drive Cycle and then return for another go at checking for codes...I failed the 1st smog test, if no codes or CEL, I'll retest...due by 6/23!!
Wish me luck and thanks for the replies
Best regards
DQ

 

That's good news! Glad to hear it.
2 things:
1) most city/state police stopped ticketing for stickers during Covid, not sure what yours are doing but I have hears that Dallas cops are stopping you yet.
2) I refuse to tell you how I know this, but either scanning a new sticker off another car or simply scanning yours and Photoshopping it will yeild stickers that will pass the visual test.In fact, I know of a case where a guydid that on a Chevy truck for 6 years.

 

So when my mechanic worked with it using VIDA it threw 2 1/2 pages of Codes so he just a erased everything I started off and spent the weekend working through the drive cycle...
It obviously worked because I passed so I'm safe for 2 more years
Thanks everyone for the help...
133,540 and it keeps on ticking.

Past Volvos:
1985 745 Turbo Diesel(247K miles, License plate: SMKINURI)
1995 945 Turbo Gas(224K miles)

Current: 2009 S80

 

regarding having a ton of codes - if your car hasn't been scanned in a while you may find a bunch of stuff - most of which probably doesn't point to a failed component. Some codes also need to persist to set off the CEL. Example, if you had a low voltage event, you can set a lot of codes unrelated to the charging system. If something is truly faulty the codes will simply reappear.

 

what is a drive cycle? Is it just driving the car for a week or so or is there something specific that needs to be done? My XC60 has been garaged for a month and when I took it to get emissions tested it failed. The guy asked me if the car had been repaired. I said no but it was garaged for a month while I was out of the country. He said that after sitting it needs to reset and to drive it for a week or so. I went back today (a week later) and it failed again. He said look up drive mode and follow the instructions. Googling it it looks like it means drive it for 20 minutes at 50mph, idle with AC off for 5 minutes, drive again for 20 minutes. Rinse and repeat at least three times.

Does this really solve the problem>

 

Yes - the drive cycle instructions are the fastest way to complete a drive cycle. Drive cycle instructions are different for different brands of cars - so be sure to follow a Volvo drive cycle for your year model. However most normal driving will complete a drive cycle without having to follow a specific pattern. The exception would be cars that are consistently driven only short distances or never at a constant speed - there's a portion of a Volvo drive cycle that requires the car to be driven for at least 18 minutes. (to test the Evap system)

Some scan tools have a function where you can watch the various areas get completed as you drive, and if you know what portion is not complete - you can skip to the instructions for that area rather than following the complete cycle. We would do that for our customers after an emission repair - for they always waited to the last day to get their failing test.

Here's a sample Volvo drive cycle - similar to the pattern I used to use - https://www.matthewsvolvosite.com/drive-cycle/

 

One add'l thing - most evap systems only run when the tank is more than 1/4 full and less than 3/4 full.

 

Yeah. My mechanic said that too. I wonder if I can run a tank of 100% gas (non ethanol) and will that help?

I'm also noticing that when I push the start button it just clicks. I wait a minute and try again and it starts right off. My mechanic checked it and said the battery was at 12.7 so didn't think it was a problem. What else would cause it to pause before starting in the morning. The rest of the day it's fine.

 

1. No, not needed

2. Your battery. How old is it? I imagine your service provider is testing your battery after you drive the car in. If he were to test it first thing in the morning after sitting all night, he might have a different opinion. If your battery is several years old and sat partially or mostly discharged (is this the car that sat for a month?) - a new battery might solve that click.