722.6 Solenoid Kit 2004-2005, remanufactured and ready to install. Fits the 722.6. Ships fast from the USA.
A 2004 or 2005 Mercedes C230 with the 1.8L supercharged four and the five-speed automatic uses the 722.6 transmission. When one of these cars starts refusing to upshift, drops into a single gear with the check engine light on, or flares between second and third, the six solenoids on the valve body are a frequent cause. This remanufactured set replaces all six at once and is listed specifically for the 2004-2005 C230 1.8L, so you are not guessing from a generic 722.6 listing.
The C230's transmission control module decides when to shift based on throttle, speed and load, then fires solenoids to make it happen. Three of the six are simple switches that each trigger a shift pair: 1-2 and 4-5 share one, while 2-3 and 3-4 each have their own. Those three only switch on during a shift and rest off in gear. The other two are proportional pressure regulators. One sets the working pressure that clamps the clutches, the other sets shift pressure, which decides whether a shift feels crisp or mushy. The last solenoid applies the torque converter clutch. Because these are electrically simple parts sitting in hot fluid, the weak points are the coil windings and the rubber O-rings that seal each one into the valve body.
On a car of this age, rule out the wiring before spending money on solenoids. The round electrical plug on the side of the transmission case is a known leak point: fluid travels up through the connector and into the harness, causing random solenoid codes and erratic shifting. Unplug it and look for oil. If it is wet, the connector seal must be fixed first. If it is dry, read the codes with a Mercedes-capable scan tool and check solenoid resistance at the connector against the factory specification. Because the 722.6 has no pressure test ports, a valve body bore problem can mimic a solenoid fault, which our 722.6 pressure control solenoid guide explains. For C230-specific complaints, read 722.6 Mercedes C-Class shift problems.
This set is listed for the 2004-2005 Mercedes-Benz C230 with the 1.8L engine and the 722.6 five-speed automatic. The same six-solenoid design was used across most 722.6 variants, so it may also fit other models, but this listing's fitment is the C230 1.8L only. Before installing, match your old solenoids against the photo, or send us your year and VIN and we will check it. If your car falls outside these years, compare the 722.6 solenoid kit for 2001-2005 or the 1996 722.6 solenoid kit, and see every part for this gearbox on the 722.6 and 722.9 collection.
| Fits | 722.6 2004-2005 |
| Part type | Solenoid Kit |
| Condition | Remanufactured |
| Brand | OEM |
| Reference | C230 |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
It is listed for the 2004-2005 C230 with the 1.8L engine and 722.6 automatic. Send us your VIN or compare your old solenoids to the photo to confirm.
Six solenoids: three shift solenoids, the modulating and shift pressure regulating solenoids, and the torque converter lockup solenoid.
Check the round case connector for oil first. A leaking connector is a common cause of solenoid codes on the 722.6. If it is dry, read codes and test solenoid resistance.
If there is oil in the plug, yes. Fix the seal at the same time, otherwise fluid will keep reaching the harness and the codes will return.
Clear the codes and reset the transmission adaptations with a scan tool, then road test so the module relearns shift timing.
