I’ve got a real head-scratcher here with a 2009 Volvo S80 3.2L (auto trans) and could really use some insight from anyone who’s been down this road before.
The Main Issue:
Car will not crank or turn over. Insert key into dash, depress brake pedal, push to start — nothing. Just warning lights on the dash. No engine noise, no click, no attempt to start. Also, key gets stuck in the dash and cannot be released unless I physically remove the ignition module. Getting “Shift to P” warning even though shifter is already in Park. Shifter override works to move between gears, but it doesn’t clear the warning.
Timeline & Context:
- Problem started about 2 months ago on a very cold day while driving around 35mph.
- Dashboard lit up, engine died mid-drive, but electronics stayed on.
- Was able to coast to the side of the road safely.
- Tried restarting immediately — car would not crank, no engine noise at all, only warning lights.
What I’ve Done So Far:
✅ Brand new battery installed (old one tested and was fine).
✅ Alternator tested by AAA driver and said was good.
✅ Starter was working fine up to the day of the event.
✅ Checked and replaced critical fuses and relays (all appeared fine).
✅ Pulled CEM and ECM — no visual signs of corrosion or water intrusion.
✅ Battery disconnected, terminals touched together for full discharge/reset.
✅ Key fobs both functional, locks and electronics all respond.
✅ Shifter linkage inspected and overridden manually — still stuck in “Shift to P” warning.
✅ Vehicle will not let me clear codes — prompts that car must be started first.
Known Electrical Issue (possible related?):
- Long-standing Low Beam Headlight warning. Replaced bulbs twice, both sides — bulbs work briefly then cut out. High beams function fine.
- Vehicle has a leak in windshield seal, and water has been known to get into footwells.
- I’ve already removed the carpets and made sure everything is dry before continuing troubleshooting.
- Pulled up footwell wiring and saw no obvious corrosion, loose plugs, or frayed wires. But I know water intrusion can be a slow killer.
Volvo Vida/Dice Scan Results:
Getting 22 codes. Major modules showing red (offline or no comms):
- CEM, DIM, PEM, CCM, DDM, PDM
Key codes: - U015100 – DIM lost communication with SRS
- U042268 – Invalid data received from CEM
- P061E67 – Internal control brake signal performance failure
- U010000, U010100, U014000, U012100, U015100 – Lost comms with multiple modules
- B10A202 & B10A211 – Crash input signal failure (BUT CAR HAS NEVER BEEN IN AN ACCIDENT)
All other modules show green, but I’m guessing with the CEM throwing fits, it’s cascading failure.
Symptoms Right Now:
- Insert key, brake pedal down, hit start — no crank, no click.
- All electronics work (blower, radio, AC, power locks, etc).
- Key stays stuck unless I remove the ignition module manually.
- “Shift to P” light on, even in P.
- Occasionally throws ABS and Parking Brake Service Required warnings.
- Immobilizer Active message pops up.
What I’m Looking For:
I’m not trying to dump a ton of cash into a 20-year-old Volvo worth maybe $1,000. But if I can get it back running without replacing the whole CEM or full harness, it would be worth it.
My Main Questions:
- Is there a specific area in the wiring harness (maybe under dash, behind kick panels, under fusebox, etc.) that’s known to corrode and cause this kind of cascade failure?
- Is it possible the Immobilizer is stuck active because of faulty data from the CEM or shifter position sensor?
- Could a bad Brake Position Sensor, shifter microswitch, or SRS fault prevent the car from releasing the key and starting?
- Are there any workarounds or tricks for bypassing the immobilizer or jump-starting the CEM just to get the car to turn over for testing?
I’m grateful for any feedback or troubleshooting tips you all can offer. This car was running perfectly fine before this happened. Just want to get her started without throwing unnecessary parts at it.
Thanks in advance!
Jim