賓士原廠技術通報-W204/C300

- Hard 1-2 shift or hard torque converter lockup clutch engagement -

Topic number	GI27.00-P-044014
Version	2
Design group	27.00 General
Date	03-11-2010
Validity	Transmission 722.9
Reason for change	Remedy revised

Complaint

The customer complaint "Hard shift, presumable the 1-2 shift, occurs when moving off" is often received even though the problem is hard engagement of the torque converter lockup clutch (KÜB) in the start-off procedure.

In order to permit a clear diagnosis, restrict the 1st gear before moving off.

If a jolt occurs at the point where the state of the torque converter lockup clutch changes from "open" to "slipping", then the cause should be sought in the control of the torque converter lockup clutch.

Cause

Control of torque converter lockup clutch engagement not ideal.

Remedy

1. Via DAS menu item "Initial startup", perform transmission software update and then perform SCN coding.
   
2. Via DAS menu item "KÜB adaptation", adapt the torque converter lockup clutch according to the coolant temperature and torque window.
   
3. Then perform a test drive.

If the complaint is still present, first work through the diagnosis tree for transmission 722.9 (GI27.00-P-035661) and, if the complaint persists, please contact Technical Product Support and attach a current quick test report and the control unit log to the TIPS case.

Symptoms

Symptom

Power transmission / Power transmission, function / Jolting/shuddering during start-off

Power transmission / Automatic transmission / Automatic transmission - function / General

Power transmission / Automatic transmission / Automatic transmission - function / Shifts

Power transmission / Automatic transmission / Automatic transmission - function / Poor shift quality

Operation numbers/damage codes

Op. no.	Time	Damage code	Note
Operation text
		5455390