Radio switches on and off and lamps in instrument cluster flicker while driving; and engine does not start - AF54.10-P-6004A

MODEL 163.113 /154 /172 /174 1A as of 145273, 163.113 /136 /154 /172 /174 1X as of 707755 up to 717497

Damage code	Cause	Remedy
54 019 74	Nut on line connector for circuit 30 (X4/37) does not apply sufficient pressure at contact point, because nut makes contact with line terminal in shoulder area. This leads to occasional voltage drop.	1 Check contact at X4/37 line connector on firewall Replace terminal block nut if it makes contact with the line terminal in the shoulder area (arrow). ↓
		2 Open engine hood and position upright	AR88.40-P-1000GI
		3 Cover right fender with protective fender cover.
		4 Turn ignition key to position "0"
		5 Disconnect ground lead from battery.	AR54.10-P-0003A
		6 Remove protective cover from positive pole on battery and install on negative pole Plug-in holes on the protective cover are located below the sticker.
		Model 163.113/174 only 7.1 Disconnect positive lead for suction fan control module from positive pole of battery
		Model 163.113/174 only 7.2 Remove fuse holder of suction fan at front at shield and remove lines from shield
		8 Unscrew mounting screw from shield
			*BA54.10-P-1018-01C
		9 Remove clamping wedge from retaining bracket
		10 Unhook retaining bracket Press downward and remove
		11 Move battery and shield in direction of engine until terminal block X4/37 is accessible
		12 Remove nut (1) from X4/37 line connector
		13 Install new nut at X4/37 line connector.
			*BA54.10-P-1019-01C
		Ensure that cable is correctly routed. Battery line (3) is located behind positive pole (2) of fuse and relay module.
		14 Wax lines and terminal block X4/37
		15 Install battery with shield and all detachable body components in opposite order
		16 Remove protective fender cover.
		17 Mark retaining bracket of battery with blue color. To indicate that new nut is installed.
		18 Read out stored DTC with STAR DIAGNOSIS and erase.

Fig 1: Locating Shoulder Area Of Nut And Terminal

Fig 2: Identifying Battery And Positive Lead For Fuse And Relay Module

Battery

Number	Designation		Model 163
BA54.10-P-1018-01C	Bolt, shield to body	Nm	20
BA54.10-P-1019-01C	Nut for line connector on fire wall	Nm	15

Parts ordering notes

Part no.	Designation	Quantity
163 546 00 72	Nut for line connector	1
000 986 33 70 10	Wax preservative	1