engine

Oil Level Sensor

for 2012 Mercedes-Benz S65 AMG 6.0L V12 BiTurbo M275 · RWD

Difficulty

Moderate

Time

1.1 h

Tools

Steps

✓Fact-checked. Built from OLP's spec database, then independently fact-checked line by line with every correction applied. Master-tech sign-off by Chris Hackleman is queued. Cross-check torque values against the factory manual, and stop if anything looks unsafe. How our data is made.

Replace the oil level sensor located in the oil pan of the M275 V12 BiTurbo engine to restore accurate oil level monitoring and eliminate warning lights.

Warnings

⚠️Engine and oil must be completely cool before starting work. Hot oil can cause severe burns.

⚠The M275 V12 engine requires special care with electronics. Disconnect battery before beginning work to prevent sensor circuit damage.

⚠Oil will drain from sensor mounting location. Have drain pan positioned before removal.

ℹ️The oil level sensor on this engine is located on the passenger side of the oil pan and requires partial oil drain or vehicle positioning to minimize spillage.

Tools required

Vehicle lift or jack standsEssential

Torque wrench (10-50 Nm range)Essential

22mm wrench or socketEssential

Oil drain pan (minimum 10 quarts)Essential

Metric socket set

Ratchet and extensionsEssential

Plastic trim removal tools

Clean shop rags

Wire brush (nylon)

Brake cleaner or solvent

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Parts

Oil level sensor × 1 — A0011531232 or equivalent OEM sensor
Oil level sensor seal/O-ring × 1 — Usually included with sensor
Engine oil (if needed for top-up) × 1 — Mercedes-Benz 229.5 5W-40

As an Amazon Associate and Autel/ANCEL partner, OLP earns from qualifying purchases — how we link. This never changes the specs we publish.

Fluids

Mercedes-Benz 229.5 5W-40 — 1 qt

Preparation

Allow engine to cool completely for at least 2 hours after last operation
Disconnect negative battery terminal and wait 5 minutes for system power-down
Raise vehicle on lift or secure on jack stands at all four corners to manufacturer specifications
Remove lower engine splash shields and underbody panels for access to oil pan area
Locate oil level sensor on passenger side of oil pan (cylindrical sensor with electrical connector)
Position oil drain pan beneath sensor location

Procedure

1
Disconnect sensor electrical connector
Press the release tab on the electrical connector attached to the oil level sensor and carefully pull the connector straight off. Inspect connector pins for corrosion or damage. Clean connector with electrical contact cleaner if necessary.
2
Prepare for oil drainage
Position the oil drain pan directly beneath the oil level sensor. The sensor is located approximately 4-6 inches above the lowest point of the oil pan on the passenger side. Expect 1-2 quarts of oil to drain when sensor is removed depending on oil level and vehicle positioning.
⚠Oil will begin draining immediately upon sensor removal. Ensure drain pan is properly positioned.
3
Remove oil level sensor
Using a 22mm wrench or socket, carefully loosen the oil level sensor by turning counterclockwise. Once loosened, quickly unthread by hand and remove the sensor, allowing oil to drain into the pan. Keep sensor upright after removal to prevent additional spillage.
4
Clean sensor mounting bore
Once oil flow has stopped, use clean shop rags to wipe the sensor mounting area on the oil pan. Inspect the threaded bore for debris, metal particles, or damage. Use a nylon brush to clean threads if necessary. Do not use metal brushes that could create debris. Spray with brake cleaner and wipe dry.
5
Inspect old sensor seal
Remove and inspect the old O-ring seal from the sensor mounting bore or from the old sensor. Ensure no pieces of old seal remain in the pan threads. The seal must be completely removed to prevent leaks with the new sensor.
6
Prepare new oil level sensor
Remove new sensor from packaging and verify it matches the old sensor design. Install the new O-ring seal onto the new sensor if not pre-installed. Lightly lubricate the O-ring with clean engine oil to aid installation and prevent seal damage.
7
Install new oil level sensor
Thread the new oil level sensor into the oil pan bore by hand, turning clockwise. Ensure the sensor threads smoothly without resistance (cross-threading). Thread until the sensor seats against the O-ring, then use a torque wrench and 22mm socket to tighten to specification.
⚠Do not overtighten. The 15 Nm specification is critical to prevent oil pan thread damage or sensor cracking.
Torque spec
Oil Level Sensor15 Nm (11 lb-ft)
8
Reconnect electrical connector
Align the electrical connector with the new oil level sensor and push firmly until the locking tab clicks into place. Gently tug on the connector to verify it is securely locked. Ensure connector seal is properly seated to prevent moisture ingress.
9
Check and top up engine oil
Lower vehicle temporarily or use oil filler from above. Remove oil filler cap and add Mercedes-Benz 229.5 5W-40 oil to replace what was lost during sensor replacement (typically 1-2 quarts). Do not overfill. Replace oil filler cap.
10
Reinstall underbody panels
Reinstall all lower engine splash shields and underbody panels removed during preparation. Ensure all fasteners are properly secured.

Reassembly

Reconnect negative battery terminal and ensure secure connection
Lower vehicle to ground level
Start engine and allow to idle for 2-3 minutes, monitoring for oil leaks around sensor
Turn off engine and wait 5 minutes for oil to settle

Verification

Check oil level using dipstick with engine off and vehicle on level ground - oil should be between MIN and MAX marks
Start engine and verify oil pressure warning light extinguishes within 2-3 seconds
Using Mercedes-Benz diagnostic scanner or instrument cluster menu, verify oil level sensor shows correct reading
Check for any oil leaks around sensor location with engine running and after shutdown
Perform test drive and verify no oil level warning lights illuminate on instrument cluster
Recheck oil level after test drive and top up if necessary to maintain proper level