Preparation for DTC Readout

1. Review 21, 22, 23 2. Connect Hand-Held Tester (HHT) to data link connector (X11/4) according to connection diagram (see section 0). 3. Read out DTC memory and actual values for BAS system. 4. Read out DTC memory for traction systems (ABS, ASR, ESP). 5. Perform Function Test via the HHT. 6. Ignition: ON DTC readout is not possible using an impulse counter scan tool. In case of complaint, and no fault is present in system, perform 23 in its entirety.

Test Equipment; See MBUSA Standard Service Equipment Program

Description	Brand, model, etc.
Digital multimeter	Fluke models 23, 77 III, 83, 85, 87

DTC	Possible cause	Test step/Remedy 1)
-	No fault in system	In case of complaint: 23 (entire test).
	BAS control module (N48) Solenoid valve (A7/7y1)(BAS) short to ground Circuit 30, open circuit	Replace BAS control module (N48), 23 4.0 23 1.0
	Battery voltage too low, circuit 87	23 1.0
	Battery voltage excessive, circuit 87	23 1.0
	Incorrect engine control module (ME-SFI)	Read out DTC's for engine control module, Code engine control module.
	CAN communication with traction systems control module (N47) interrupted CAN communication faulty overall CAN signal from stop lamp switch (S9/10), interrupted CAN signal from VSS (wheel rpm) or ABS, interrupted	9.3, 13/1
	Release switch (BAS) (A7/7s1), open circuit Release switch (BAS) (A7/7s1), short circuit Release switch (BAS) (A7/7s1), short to ground	See Actual Values, via HHT.
	Release switch (BAS) (A7/7s1), plausibility	See Actual Values, via HHT.
	Release switch (BAS) (A7/7s1), redundancey	See Actual Values, via HHT.
	Membrane travel sensor (BAS) (A7/7b1), open circuit or short to ground Membrane travel sensor (BAS) (A7/7b1), short circuit Membrane travel sensor (BAS) (A7/7b1), short to ground ot open circuit	23 5.0
	Membrane travel sensor (BAS) (A7/7b1), plausibility	23 5.0
	Membrane travel sensor (BAS) (A7/7b1), membrane speed	23 5.0
	Stop lamp switch (S9/1) plausibility, membrane comparison Stop lamp switch (S9/1) plausibility, release switch comparison	23 5.0 See Actual Values, via HHT.
	Solenoid switch (BAS) (A7/7y1), short to ground Solenoid switch (BAS) (A7/7y1), short circuit to positive + Solenoid switch (BAS) (A7/7y1), short circuit Solenoid switch (BAS) (A7/7y1), open circuit	23 4.0

1) Observe Preparation for Test, see 22.