Odd electronics issue; time for a new fuse box BCM/CCM? Topic is solved

[benpineapple]

Good morning!

Had a very odd electronics issue on my morning commute (30 miles, most of which is freeway):
- While cruising at 75MPH, cruise control drops out, wipers start sweeping, "Anti-Skid Service Required" message appears, and transmission indicator disappears from dash display (instead of saying "D" a long dash appears in its place)
- ~3 miles later "Transmission Service Required" message appears as well
- Motor's performance feels withdrawn, am able to keep cruising at 75MPH until next exit

I safely pull into a gas station, shut the car off, unplugged the 3 connections on the fuse box (unit under glovebox, above PS floor mat), and plugged them back in. Then I plugged in my OBD reader and got the following codes:

- [Confirmed] P0600, serial communication link
- [Pending] U0103, lost communication with gear shift module
- [Pending] P0863, TCM communication circuit

I reset codes, turned car back on, and the car drove as normal with no issues for the remaining 5miles to my office. The anti skid and transmission messages did not reappear.

Relevant backstory: this is my first commute since getting my car back from the body shop last week. They repaired my rear bumper, and rear DS quarterpanel. I got hit at low speeds in a parking lot a month ago by someone cutting across lanes, insurance covered all my repairs thankfully. The body shop also thoroughly detailed the interior of my car, and I'm thinking maybe it's as simple as a tech bumped the fuse control box really hard or something? I recall on my first drive home after buying the car, my partner kicked the control box on accident while stretching out or something, and the car went into limp mode. After some roadside googling, found the fuse/relay box could be the culprit and fixed the issue by simply unplugging, cleaning all connections, and replugging it back in.

What else should I take a look at? I think just shutting the car off and turning it back on may have been what cleared the messages on the dash display. I'm also wondering if this is a bigger issue with more going on? Let me know if you need any more info or clarifications. Will update here after my commute home this afternoon.

Thanks!

[RickHaleParker]

I safely pull into a gas station, shut the car off, unplugged the 3 connections on the fuse box

Not odd, it is a common problem.

That is not a Fuse box. It is the CEM (Central Electronic Module) with fuses. The Volvo CEMs are infamous for the CEM connections going wanky. Clean the connectors with MAP cleaner or electrical contact cleaner. Disconnect battery when doing so.

[benpineapple]

I safely pull into a gas station, shut the car off, unplugged the 3 connections on the fuse box

Not odd, it is a common problem.

That is not a Fuse box. It is the CEM (Central Electronic Module) with fuses. The Volvo CEMs are infamous for the CEM connections going wanky. Clean the connectors with MAP cleaner or electrical contact cleaner. Disconnect battery when doing so.

I could have sworn it was called the CEM. A quick google search kept showing me different names with a picture of the CEM.

Yeah I didn't have the issue on my drive home yesterday, or my drive to work this morning. Pretty sure it just got bumped or maybe some solvent spray got on it. Going to pull it and clean with some electrical contact cleaner I have.

Thanks!