Renault Symbioz RJB — Problems & Common Faults

A 1.3-litre turbo developed with Daimler, with a timing chain and clearly improved reliability over the 1.2 TCe. Weak points are the wastegate linkage of early years (before the mid-2020 factory revision), the leaking thermostat housing and the intake-valve coking typical of direct injection. Ignition coils and spark plugs fail earlier than expected — a check from 60,000 km is sensible. With good oil care a solid, everyday-capable engine.

• !! Timing Chain Early Wear from 120,000 km

  The H5H 1.3 TCe also shows initial timing chain rattling in 2019 models after 50,000–70,000 km. Chain tensioners in particular wear prematurely and must be replaced.

  Symptoms: Rattling on cold start, clattering on load changes, camshaft control fault code
  800–2,000 $
  Ad H5H 1.3 timing chainRenault 1.3 TCe timing chainH5H chain tensioner
• !! Wastegate Failure After 80,000+ km from 60,000 km

  The wastegate valve of the H5H 1.3 TCe turbocharger wears after 80,000–100,000 km, causing power loss and increased oil consumption.

  Symptoms: Power loss, no boost build-up, whistling from the turbo area
  300–2,500 $
  Ad H5H 1.3 turbochargerRenault 1.3 TCe TurboH5H wastegate actuator
• !! Thermostat housing leak from 70,000 km

  The thermostat housing and its seals start to leak and coolant is lost without a visible external leak. Ignored, it risks overheating. The fault pattern and the part are known from the identical Mercedes engine.

  Symptoms: Coolant loss without visible leak, overheating warning, fault code P0128
  300–900 $
  Ad thermostat housing 1.3 TCethermostat 1.3 TCethermostat seal 1.3 TCe

+ 2 more engine weaknesses + vehicle weaknesses

Renault's full hybrid system combines a simple, robust 1.6-litre naturally aspirated engine with two electric motors and a 1.2 kWh battery — the combustion engine without direct injection is constructively solid. Early build years show a known shaft seal issue between gearbox and electric motor that causes oil leaks. Overall an economical and reliable drivetrain with correct servicing.

• !! Recall 0ET1: Electric Motor Primary Shaft O-Ring from 30,000 km

  Recall 0ET1: An O-ring on the primary shaft of the electric motor inside the DB1 multimode gearbox fails, allowing gearbox oil to contaminate the e-motor. In mild cases only the temperature sensor is damaged (€300–500); in severe cases the e-motor windings are destroyed (up to €8,000). 155,825 vehicles built April 2019 – September 2022 affected. Renault replaces the original O-ring with a reinforced X-ring.

  Symptoms: Gearbox overheating warning, power limitation, 'electric motor fault' warning, internal oil loss without visible external leak
  0–8,000 $
• !! Electric Motor Failure from Oil Contamination from 50,000 km

  When the O-ring on the electric motor's primary shaft fails (recall 0ET1), gearbox oil enters the integrated e-motor and destroys its windings. On vehicles built 2019–2022, damage can occur without warning. Repair costs outside warranty: €3,000–8,000. Vehicles built after September 2022 have the X-ring fix from the factory.

  Symptoms: Warning 'electric motor fault', limp-mode speed limitation, vehicle stranded, gears cannot be engaged
  3,000–8,000 $
  Ad Renault E-Tech electric motor statorDB1 electric motor windingsH4M-FHEV electric motor replacement
• !! O-Ring Failure: Gearbox Oil Contaminates E-Motor (Recall 0ET1) from 35,000 km

  The O-ring on the electric motor's primary shaft inside the DB1 multimode gearbox is poorly manufactured and allows gearbox oil to enter the e-motor internally. The gearbox remains externally dry. Recall 0ET1 covers 155,825 vehicles (Apr. 2019 – Sept. 2022). Early detection means a free seal replacement; advanced oil damage means a destroyed e-motor, costing up to €8,000.

  Symptoms: Gearbox overheating warning, low gearbox fluid level without visible external leak, e-motor temperature fault codes
  300–8,000 $
  Ad Renault E-Tech O-ring primary shaftDB1 gearbox oil seal X-ringH4M gearbox seal electric motor

+ 6 more engine weaknesses + vehicle weaknesses

1.8-litre four-cylinder full hybrid of the second E-Tech generation: 80 kW combustion output, 172 Nm, combined with a 36 kW e-motor and a 15 kW starter-generator on the clutchless multimode gearbox (four combustion and two electric ratios). The battery grew to 1.4 kWh. In normal driving the gearbox shifts smoothly and discreetly; when the engine revs up to recharge the battery, vibration and noise become clearly noticeable, and a brief jolt can come through under hard acceleration. Documented real-world consumption ranges from 4.7 to 6.4 l/100 km. Long-term data is still pending given the 2025 market launch.

• !! Loss of drive with fault message under full load (limp mode)

  Under heavy load, such as a long uphill climb at full throttle after switching out of regen mode, the drivetrain control can briefly cut power and display a gearbox fault message. The car drops into a limp-home mode for around 30 seconds before behaving normally again after a restart.

  Symptoms: Sudden loss of power under full load on an incline, an automatic-transmission fault message on the display, an accompanying drone from the drivetrain; usually resolves after switching the car off and on again.
  0–0 $
  Ad Renault Symbioz spare part
• !! 12V system too weak — hybrid control units fail to initialize

  If the 12V battery voltage drops too far, the hybrid control units cannot initialize correctly. The car then refuses to start even though the high-voltage traction battery is sufficiently charged.

  Symptoms: Vehicle fails to start despite a charged hybrid battery; 12V battery repeatedly flat, sometimes overnight; battery-saving-mode warning messages.
  120–350 $
  Ad 12V starter battery SymbiozRenault E-Tech control unit initialization
• ! Multimode dog-clutch gearbox: clunk and rev flare when the engine engages from 8,000 km

  When switching from pure electric driving to combustion-engine operation (e.g. on cold start or around 40 km/h), a metallic clunk or cracking noise can occur sporadically in the clutchless multimode dog-clutch gearbox, sometimes with a brief flare in engine speed.

  Symptoms: Metallic clunk when the combustion engine engages first gear; briefly noticeable rev flare when switching from electric to combustion operation, especially on a cold engine.
  150–900 $
  Ad multimode dog-clutch gearboxdog clutch actuator E-Tech