Listing of Test Steps

1	Test equipment	connect/disconnect.
2.0	Throttle control linkage	check throttle valve for free movement and condition. Lubricate bearings, gate levers and ball sockets.
2.1	Idle stop	check, adjust
3	Ignition timing with and without vacuum Engine: at Idle	check (see Test and Adjustment Data, Section A).
4	Engine rpm (at Idle)	check.
5	On-off ratio control	check.
6	CTP speed under load	check in TR "D" (with service and parking brake applied) and with all consumers turned on.

Equipment

Engine analyzer 1)	Bear DACE (Model 40-960) Sun MEA-1500MB
Digital multimeter 1)	Sun DMM-5 Fluke Model 23 with 80i-410 current probe

1) Available through the MBUSA Standard Equipment Program.

Note: Two adapters 900 589 01 15 00 are required for testing engine 120.

Connection chart for test equipment without diagnostic adapter for two circuit ignition systems

Engine analyzer version	Cylinder no. setting on engine analyzer	Type of measurement	Circuit on Diagnostic socket			Trigger clamp on ignition cable	kV-Clamp on ignition cable ignition circuit
			X11 Engine 119	X11/2 Engine 120 L.	X11/3 Engine 120 R.
Bear DACE (Model 40-960) SUN MEA-1500MB	Engine 119 : 4 Engine 120 : 6	RPM/ dwell angle of Ignition circuit	T1/1		T1/1
		RPM/ dwell angle of Ignition circuit		T1/2
		Timing of Ignition circuit	T1/1		T1/1	Cylinder 1	Engine 119 : T1/1 Engine 120 : T1/1
		Timing of Ignition circuit	T1/2	T1/2		Engine 119 : cyl. 2 1) Engine 120 : cyl. 12	Engine 119 : T1/2 Engine 120 : T1/2
		Oscilloscope primary/secondary and voltage at terminal 15/1 of Ignition coil	T1/1		T1/1	Engine 119 : cyl. 1 Firing order 1-4-6-7 Engine 120 : cyl. 1 Firing order 1-5-3-6-2-4	Engine 119 : T1/1 Firing order 1-4-6-7 Engine 120 : T1/1 Firing order 1-5-3-6-2-4
		Oscilloscope primary/secondary and voltage at terminal 15/1 of Ignition coil		T1/2		Engine 119 : cyl. 5 Firing order 5-8-3-2 Engine 120 : cyl. 12 Firing order 12-8-10-7-11-9	Engine 119 : T1/2 Firing order 5-8-3-2 Engine 120 : T1/2 Firing order 12-8-10-7-11-9

1) On engine 119 subtract 90 °crankshaft from measured value., Example: measured: 107 °crankshaft, 107-90= 17 °crankshaft timing

Note: The on-off ratio control system test should not be performed on a very hot engine, for example, after a fast drive or after an output test on a dynamometer.

Test step/Test sequence	Test condition	Nominal value	Possible cause/Remedy 1)
1 Connect test equipment according to diagram	Ignition: OFF	-	-
2 Check condition and free movement of throttle linkage and throttle valve	Ignition: OFF Actuate throttle linkage	Smooth operation, no binding should be evident.	Lubricate all bearings and ball sockets.
2.1 Check idle speed position	Ignition: OFF Accelerator pedal at CTP	Throttle valve lever must rest against CTP stop (audible contact).	Adjust CTP stop on engine (SMS, Job No. 30-1010)
3 Check ignition timing with and without vacuum	Engine: at Idle Selector lever in "P" Climate control system: OFF	See Test and adjustment data (section A)	Check ignition system (DM Engines, Vol. 2 - 5.2 or 5.3)
4 Warm engine oil to operating temperature	Engine rpm: maintain at approx. 3000 rpm	Engine oil temperature approx. 80 °C	-
5 Check CTP rpm	Engine: at Idle Selector lever in "P", Climate control system "OFF".	See Test and adjustment data (section A)	Test program: Check EA/CC/ISC system (DM Engines, Vol. 3 - 6.2 or 6.3), Check CC/ISC system (DM Engines, Vol. 3 - 7.1)
6 Check on-off ratio control system	Selector lever in "P", Climate control system OFF. Disconnect and plug purge line (A or B) at switchover valve (Figure 1, 3 and 4). Reconnect line after measurment. Engine: at Idle	See Test and adjustment data (section A)	Check electrical components with socket box tester (DM Engines, Vol. 2 - 3.1 or 3.2)
7 Check CTP speed under load	Engine: at Idle TR "D" (service and parking brake applied), Switch on all electrical consumers, Turn steering wheel to full lock.	Engine must continue to idle within specified range.	Test program: Check EA/CC/ISC system (DM Engines, Vol. 3 - 6.2 or 6.3), Check CC/ISC system (DM Engines, Vol. 3 - 7.1)

1) Observe Preparation for Test, see 22 .