ETM/Volvo Dealer questions

[nolyaw]

I have a 1999 C70 Conv. and it is 21 days from being out of its 10 year ETM warranty. A couple of weeks ago, I had no cruise, loping idle, surging, ETS light on , along with the CEL. I did an overhaul by replacing the entire PCV system, cleaning the throttle body and elbow, along with the intake manifold. I disconnected the battery while I did the service. When I started the car, it ran like a top, as good as new. This was about 6-700 miles ago. No lights, no problems. Well, I am going to the Stealer on Thursday, to have it scanned for ETS/M codes, so I can get a new ETM. They want $160, 1.5 hrs. labor to do a "diagnostic check". It really takes that long to scan it? B.S.! My question is will the computer retain the codes from before, even after disconnecting the battery? Or will they stay in memory until they are reset?

[nolyaw]

No one knows if the codes remain after a battery disconnection?

[FlyingVolvo]

I do know Volvo dealers tend to charge a crap load even for something like a diagnostic because they "do it by the book" which means however long the book (or they) thinks it should take, it takes... and they charge you for it.

As for the codes, I'm not too sure. I know disconnecting the battery will clear check engine lights, and those are stored in the ECU. I would guess that the ETS codes would also be in the ECU, and possibly cleared.

Hopefully others have some input. This forum seems kind of dead-ish... sucks because people are still having issues, myself included!

[ChrisatXeMODeX]

Depending on whether it is a soft or a hard code, soft codes will be lost after a battery is disconnected. ETM codes are stored primarily in the ECM, recall software made almost all of the ETM failure codes “soft”.
Unless you have a permanent failure within the ETM it is unlikely that you’ll have any codes stored even without disconnecting a battery.