Random Vehicle Level (LI32.50-P-045833)

Publication date: 2009-01-27
Reference number: LI32.50-P-045833
Supersedes refnos: 32.50/35A, 32.50/35C

RANDOM VEHICLE LEVEL

TECHNICAL SERVICE BULLETIN

Reference Number(s): LI32.50-P-045833 Version 1 (P-B-32.50/35C, October 29, 2008), Date of Issue: January 27, 2009

Mercedes-Benz:	Model 215.373/374/375/376/378/379; Model 220.067/083/170/173/174/175/176/178/179/183/184, Equipped with Code 487 (Active Body Control); Model 230.471/472/474/475/476/477/479, Up to VIN F118817
Design Group:	32.50 Active body control (ABC)
Reason For Change:

Superceded Bulletin(s): P-B-32.50/35B, Date of Issue: February 22, 2008

COMPLAINT

Suspension level randomly lowering while driving and/or rapid sporadic level changes shortly after stopping the vehicle

CAUSE

N/A

REMEDY

Replace the body acceleration sensors (reference WIS document GF32.31-P-4100A), with a manufacturing date greater than 02 W 01 (Year 2002, week 01) (Fig 1).

NOTE: Do not replace any other ABC suspension components.

In both of the above scenarios, vehicle level changes typically occur intermittently and predominately after driving for extended periods. The vehicle's level adjusts without obvious cause, and usually quickly moves upwards or downwards, and then rapidly corrects back to the specified level.

Random level movements (while driving) only occur when the ABC suspension system is in Active mode (i.e. when the vehicle is in motion). Thus, the above mentioned level movements cannot occur when the ABC system is in Passive mode (i.e. vehicle stopped). Since the ABC system does not switch to Passive mode until a few seconds after the transmission gear selector is positioned into Park or a significant braking torque is applied for several seconds, sporadic level conditions may exist shortly after stopping the vehicle. Random level conditions may also exist shortly after stopping the vehicle if the vehicle is stationary but an insufficient amount of braking torque is applied, thus causing the system not to switch to Passive mode.

NOTE: The random level control is the result of tolerance contact issues on the printed circuit board of the body acceleration sensors [B24/3-front left, B24/4-front right, B24/5-rear left (Model 230), B24/6-rear right (Model 220/215)], in combination with the sensors heating up after an extended period of driving. The contact issue can result in a higher internal resistance on the printed circuit board causing the sensor to output an incorrect signal, thus initiating an ABC adjustment.

NOTE: The following allowable labor operations should be used when submitting a warranty claim for this repair. This information has been generated on February 22, 2008. Please refer to Netstar -> Star TekInfo -> Star Time for the most current labor time allowance.

ATTACHMENTS

Fig 1: Acceleration Sensor Manufacturing Date

SYMPTOMS

Suspension System Function / Chassis/suspension / Vehicle level too low / Suspension/Dampening /

Vehicle lowers / ABC Function / Chassis/suspension / Active body control / Suspension/Dampening /

ABC Function / Chassis/suspension / Active body control / Regulates without obvious cause / Suspension/Dampening /

PARTS

Part number	Designation	Qty	Note	EPC	Non- EPC
A004 542 35 18 28	Acceleration Sensor	3			X

WORK UNITS

Op. no.	Operation text	Time	Damage code	Note
32-7530	ACCEL. SENSOR - FRT. LEFT FOR ACT. BODY CONTROL (ABC), REPLACE	0.2 hrs.	32562 73	Model Indicator (s): J1, J2, J3, M1, M2, M4, M5, M6, M7, M8, M9, N1, N2, N3, N4, N5, N6, R1, R2, R3, R4, R5, R6, R7
32-7531	ACCEL. SENSOR - FRT. RIGHT FOR ACT. BODY CONTROL (ABC), REPLACE	0.2 hrs.		Model Indicator (s): J1, J2, J3, M1, M2, M4, M5, M6, M7, M8, M9, N1, N2, N3, N4, N5, N6, R1, R2, R3, R4, R5, R6, R7
32-7533	ACCEL. SENSOR - REAR RIGHT FOR ACT. BODY CONTROL (ABC), REPLACE	2.2 hrs.		J2, J3, M1, M2, M4, M5, M6, M7, M8, M9, N1, N2, N3, N4, N5, N6
32-0000	ACCEL. SENSOR - REAR LEFT FOR ACT. BODY CONTROL (ABC), REPLACE	0.6 hrs.*		R1, R2, R3, R4, R5, R6, R7 * Maximum time allowed with a separate time punch.

WIS-REFERENCES

Document number	Title	Note	Allocation
GF32.31-P-4100A	Body acceleration sensor, location / task / function		Remedy