Left and right stalk no functions. Replaced stalk nothing. 2006 xc90 V8

aaron1611 · Post by **aaron1611** » 03 Feb 2025, 11:10

Hi there everyone. My left stalk has zero function and message center screen is locked. Replaced it with a new Volvo stalk and nothing. Right stalk zero function except low speed wiper. I don't want to throw anymore parts at it. What should I be looking for now? Oh, all steering wheel buttons work fine.

Post by **ggleavitt** » 04 Feb 2025, 21:48

Steering wheel module is what the stalks and wheel switches interface to (stalks connect directly into the SWM assembly). Might be worth removing both stalks and making sure you don't have a smooshed connector pin or the like, they're pretty small. That you have wheel buttons working but not stalk working properly might be something towards the stalk interface but that's just a guess (wheel buttons interface to SWM via contact reel I think). SWM is an active module, outputs LIN bus to CEM for follow-on activation (like turn signal) so you know some downstream CEM actions are occurring but not all of them.

You have a chance to get a Volvo centric code reader on this vehicle? Might be something there. Last but not least, ever try a disconnect of the battery and a reconnect a little later to see if it's just something funny in the module software? Probably wouldn't hurt at this point.

Pretty much all I can think of, might be a direct swap for matched parts range SWM (someone can correct this assumption) if it's broke, think I saw a post or two and will edit if I can find.

aaron1611 · Post by **aaron1611** » 07 Feb 2025, 08:03

Good morning, thanks for your response. I'll disconnect the battery today to see if that resets it. Otherwise, I'll plug vida/dice to see if it brings up anything.

Post by **ggleavitt** » 07 Feb 2025, 08:40

I would absolutely pull both stalks and inspect the connector pins on the SWM, that's another easy check.

aaron1611 · Post by **aaron1611** » 10 Feb 2025, 11:43

disconnecting the battery didn't work. Vida says that the communication with the SWM control module signal missing. CEM-DD50. other codes were also present but this seems most likely. The pins on the left stalk looked fine, none bent.

Post by **ggleavitt** » 10 Feb 2025, 12:32

CEM does not see an active LIN bus from the SWM I guess. Odd about the wheel buttons working with only select stalk functions under this scenario, thought everything went through the same LIN path.

: LIN Bus_1_XC90.jpg (28.16 KiB) Viewed 2233 times

https://www.swedespeed.com/threads/stal ... day.671512, might find something here. UK Volvo site had a similar issue-, https://www.volvoforums.org.uk/showthread.php?t=299854 with some logical troubleshooting to unplug one of the stalks and try the functions on the other.

**No possibility of water intrusion on the CEM? Was an older style cover for MY05 into 06 in the plenum under the drain screens, had an issue with leaking with a reworked replacement cover issued as a TJ. Given that this is an '06 (issue covers chassis 134000-327999 ??), might not hurt to see about the cover and make sure the CEM is not wet on top. Some history here:

inrd-pe10025-44260p.pdf: (2.87 MiB) Downloaded 38 times

Post by **ggleavitt** » 10 Feb 2025, 15:40

See wiring diagrams in this thread if you want some references: viewtopic.php?t=103981

aaron1611 · Post by **aaron1611** » 11 Feb 2025, 07:56

I think I'm going to swap out the SWM, quick question though. Does this require the dealership to program the software or is a plug in play?

Thank you,

Post by **ggleavitt** » 12 Feb 2025, 11:54

Sorry, was looking around to see if the answer to this was straight forward. I cannot see anything calling out a software reload specific to the SWM itself in numerous searches so I'm going to suggest that if you replace, it's a plug and play.

I "think" there should be no programming required as the SWM itself is more or less an interface module with limited function (like a seat heater module for example) but this is a guess only, just to be transparent.

aaron1611 · Post by **aaron1611** » 13 Feb 2025, 06:45

Thank you for your response. I called the dealer for the part as my local indie shop can't get it. It's &800 plus the side they need to program it as it's vin specific. Ugh.