KNOWN FAULTS · Mercedes-Benz
Known faults for the Mercedes-Benz SL (R230).
2001–2012 · Petrol
Sources are not verified in real time and no entry confirms that your car is affected.
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3 known faults with sources
Engines: SL 350 / 500 (Petrol) · SL 55 / 63 AMG (5.4 / 6.2 V8) (Petrol) · SL 65 AMG (6.0 V12) (Petrol)
Applies if: Only if fitted with SBC. Confirm by VIN.
SBC electro-hydraulic brake (Sensotronic)Brakes
- Engine / equipment
- Sensotronic Brake Control braking system: E-Class W211 and CLS C219 up to model year 2006, and SL R230
- Period mentioned
- 2002–2012
- Symptoms
- Red messages in the cluster such as “STOP VEHICLE”, “Brake defective” or “Reduced braking power – visit workshop”, a hard pedal or little assistance, and pump noises when braking or opening the door. In a complete failure only the front wheels brake, using foot force alone.
- Possible cause described
- SBC brakes by wire: a control unit calculates the pressure for each wheel and a pump with a high-pressure accumulator produces it. The hydraulic unit has a limit on operating cycles; when it is reached, it warns and reduces assistance. The pump, accumulator and wiring also fail, and old brake fluid or incorrect bleeding make it worse. Mercedes issued several recalls and, in the US, extended the warranty on several system components to 25 years.
- Check for the garage
- With any red brake warning, stop driving and call for assistance. At a Mercedes dealer: read the SBC control unit with official diagnostics, check open recalls and warranty extensions by VIN, and change the brake fluid only with the procedure SBC requires. The cycles-exhausted warning means replacing the unit, not clearing the code.
- Cost cited in the source
- No verifiable estimate for Europe. In the US, Mercedes covers the hydraulic unit and other components for 25 years with no mileage limit; ask a dealer whether your VIN has a recall or extension.A rough figure from the original database, not an up-to-date quote.
Sources from the original database
Mercedes-Benz USA (NHTSA): SBC warranty extended to 25 yearsMercedes-Benz USA (NHTSA): owner letter on the SBCWikipedia: Sensotronic Brake ControlMBWorld (W211 forum): SBC and NHTSAPeachParts (forum): the W211 drops the SBC from 2007YouCanic: SBC codes C249F and C2498
View full entryEngines: SL 350 / 500 (Petrol) · SL 55 / 63 AMG (5.4 / 6.2 V8) (Petrol) · SL 65 AMG (6.0 V12) (Petrol)
Applies if: Only if fitted with the automatic gearbox described in the record.
13-pin connector leak on the 722.6 gearboxAutomatic gearbox
- Engine / equipment
- 722.6 five-speed automatic (5G-Tronic), not the 7G-Tronic: C-Class W203, E-Class W210 and W211, CLK, S-Class W220, ML W163, SLK, SL R230, Vito and Sprinter with this gearbox
- Period mentioned
- 1996–2013
- Symptoms
- Oil around the electrical connector on the side of the gearbox, harsh shifts or slipping, delayed engagement and limp mode: the car stays in one gear (usually 2nd and reverse after a restart) and the engine light comes on.
- Possible cause described
- The plastic adapter of the 13-pin connector has O-rings that harden and let oil out. Oil can wick up inside the wiring to the gearbox control unit and damage it. If the problem persists after replacing the connector, there may be oil in the harness, a damaged wire or a conductor plate fault.
- Check for the garage
- Read the gearbox control unit codes before switching off if possible (a restart can clear them). Look for oil at the connector and, with it unplugged, on its pins and at the control unit plug. According to the service bulletin, the connector should only be removed with gearbox oil below 50 °C to avoid damaging the conductor plate, and the harness must be routed without tension.
- Cost cited in the source
- Connector adapter: about $15–20 in parts (US prices quoted in the sources), plus the lost fluid; labour extra. If oil has reached the control unit, the repair is bigger.A rough figure from the original database, not an up-to-date quote.
Sources from the original database
Brake & Front End (ALLDATA): oil leak at the 722.6 connectorMercedesMedic: replacing the 722.6 13-pin connectorMercedesMedic: P0715 and P0720 codes and limp modeMBClub UK (forum): oil in the 722.6 harness on an ML55Bob Is The Oil Guy (forum): CLK320 in limp modeThe Transmission Shop: leaks and limp mode in Mercedes gearboxes
View full entryEngines: SL 55 / 63 AMG (5.4 / 6.2 V8) (Petrol)
AMG 6.2 (M156) head bolts and camshaftsEngine (cylinder head / valvetrain)
- Engine / equipment
- M156 6.2 V8 AMG (C 63 W204, E 63 W211 and W212 until 2011, CLK 63, CLS 63, ML 63, S 63 and CL 63 until 2010, SL 63)
- Period mentioned
- 2006–2015
- Symptoms
- Coolant loss, coolant in the oil or white smoke (broken head bolts); rattle or ticking on start-up (camshaft and lifter wear).
- Possible cause described
- Cylinder head bolts that break on engines up to 2012 (Mercedes bulletin from 2011) and nodular cast-iron camshafts that wear together with the lifters, mainly on the intake side (bulletin from 2009).
- Check for the garage
- Overnight cooling system pressure test, oil analysis and camshaft inspection with a borescope.
- Cost cited in the source
- Major engine repair (several thousand euros)A rough figure from the original database, not an up-to-date quote.
Sources from the original database
Australian Car Reviews: C 63 AMG faultsAustralian Car Reviews: M156 engineAustralian Car Reviews: CLS 63 and the bolt bulletinFCP Euro: M156 faults
View full entryEngines for this model
- SL 350 / 500Petrol
- SL 55 / 63 AMG (5.4 / 6.2 V8)Petrol
- SL 65 AMG (6.0 V12)Petrol