All values measured to ground unless otherwise noted
Conn./Plug/Pin	Pin Information	Test Value	Comments
N3/10
C.28	Air pump activation signal output	Disconnect ECT sensor and connect 2.5 KOhms resistor across pin 1 and 2 of B11/4 plug engine at idle, measure to circuit 87 pin A.2 12 VDC while pump is running (approx. 2 min)
D.3	Starter activation ground signal output, energizes relay K40/4k2	Ignition on 0 VDC 12 VDC when starter turning
D.11	CAN-Bus (high side). High speed data transfer bus input and output, shares data with other ECMs	No reliable test. Check continuity to other ECMs approx. 5 VAC when data is on bus.
D.12	CAN-Bus (low side). high speed data transfer bus input and output, shares data with other ECMs	Ignition off approx. 60 Ohms between pins D.11 and D.12
E.3	Control signal output recirculated air flap actuator	Voltage varies depending on setting of air flap
E.4	Adjustable camshaft timing signal output, determines camshaft timing correction	Ignition off: 7-12 Ohms to pin A.2 Engine at approx. 2000 rpm, ECT >70 °C 1-1.5 A current draw	Insert bridge to pin A.3 (max. 10 sec.) engine runs rough or stops
E.5	EGR valve ground signal output	Connect vacuum tester. Engine at idle and ECT > 60 °C: < 1 VDC and < 10 mbar drive vehicle on rollers or road at approx. 3000 rpm: 1-7 VDC and 80-220 mbar	Use two technicians for road testing
E.10	Air pump switchover valve activation signal output	Ignition on, 0.4-0.6 A current draw
E.12	Pin not used
E.13	Injector 4 timing signal output controls fuel injection quantity (pulse width determines fuel quantity wider pulse = more fuel)	Use scope, probe tip to pin A.2 (circuit 87), gnd to pin E.1 ECT 20 °C start engine approx. t=8 msec. ECT 80 °C engine at idle approx.. t=2.7-4 msec. accelerate briefly approx. t=14 msec.	Waveform needle pulse approx. 40 Vpp, coil resistance 14-17 Ohms
E.14	Injector 2 (engine 112) or 6 (engine 113) timing signal output controls fuel injection quantity (pulse width determines fuel quantity wider pulse = more fuel)	Use scope, probe tip to pin A.2 (circuit 87), gnd to pin E.1 ECT 20 °C start engine approx. t=8 msec. ECT 80 °C engine at idle approx.. t=2.7-4 msec. accelerate briefly approx. t=14 msec.	Waveform needle pulse approx. 40 Vpp, coil resistance 14-17 Ohms
E.17	Oil level recognition signal output	Ignition on, measure to pin 37 (circuit 87) oil level: OK 12 VDC low <1 VDC
E.21	Super charger valve activation switched ground signal output	Ignition on > 1 VDC with charger off 0 VDC with charger on
E.22	Pressure sensor power output	Ignition on, approx. 5 VDC to pin E.24 (-)
E.23	Pressure sensor signal input	Ignition on > 3.5 VDC engine at idle < 2 VDC connect vacuum tester > 500 mbar
E.24	Pressure sensor ground signal output	Ignition on, approx. 5 VDC to pin E.22 (+)
E.25	Injector 1 timing signal output controls fuel injection quantity (pulse width determines fuel quantity wider pulse = more fuel)	Use scope, probe tip to pin A.2 (circuit 87), gnd to pin E.1 ECT 20 °C start engine approx. t=8 msec. ECT 80 °C engine at idle approx.. t=2.7-4 msec. accelerate briefly approx. t=14 msec.	Waveform needle pulse approx. 40 Vpp, coil resistance 14-17 Ohms
E.26	Injector 3 timing signal output controls fuel injection quantity (pulse width determines fuel quantity wider pulse = more fuel)	Use scope, probe tip to pin A.2 (circuit 87), gnd to pin E.1 ECT 20 °C start engine approx. t=8 msec. ECT 80 °C engine at idle approx.. t=2.7-4 msec. accelerate briefly approx. t=14 msec.	Waveform needle pulse approx. 40 Vpp, coil resistance 14-17 Ohms
E.28 E.29	ECT sensor signal input, low side ECT sensor signal input, high side	Ignition on, measure to pin E.29 (+) ECT at: 20 °C approx. 3.4 VDC 60 °C approx. 1.5 VDC 100 °C approx. 0.5 VDC
E.31	EA/CC/ISC potentiometer 1 signal input, determined by accelerator pedal position	Ignition on, measure to pin E.32 (-) accelerator pedal position CTP 4.0-4.6 VDC, WOT < CTP value	P/O M16.6 see also pins F.1-F.2
E.32 E.33	EA/CC/ISC potentiometer 1 and 2 power output, low side high side	Ignition on approx. 5 VDC across pins
E.34	EA/CC/ISC potentiometer 2 signal input determined by accelerator pedal position	Ignition on, measure to pin E.32 (-) accelerator pedal position CTP 0.3-0.9 VDC, WOT > CTP value	P/O M16.6 see also pins F.1-F.2
E.37 E.38	CKP sensor signal input low side CKP sensor signal input high side CKP status affects injection system timing	Start engine > 2.5 VAC, at idle > 5 VAC voltage raises with increasing rpm or use scope: sine wave 30 Vpp, t=0.7 msec. at idle
E.39 E.40	Camshaft sensor ground Camshaft sensor signal input camshaft signal affects injection system timing	Engine at idle 1.2-1.7 VDC (value alternates) or use scope square wave approx. 12 Vpp, duty cycle 80 %
E.41 E.42	Knock sensors signal input low side Knock sensors signal input high side (affects ignition system timing if "knock" is detected)	Ignition on, use oscilloscope tap on engine block see signal vary (looks like noise)	Piezo element generates increasing voltage with increasing knock signal
E.45	IAT sensor signal, reference voltage input	Ignition on, measure to pin E.48 20 °C 2.7 VDC. 40 °C 1.8 VDC, 60 °C 1.1 VDC
E.46	Hot film MAF sensor, power supply output	Disconnect B2/5, measure to pin E.48 ignition on 5 VDC
E.47	Hot film MAF sensor signal input	Ignition on, measure to pin E.48 0.9-1.1 VDC engine at idle, ECT > 70 °C 1.3-1.7 VDC voltage raises with increasing rpm
E.48	MAF sensor common ground (reference point for 5 V and 12 V supply)	Disconnect B2/5, measure to B2/5 connector pin 2 Ignition on 12 VDC
F.1 F.2	EA/CC/ISC actuator motor control signal output low side high side	Ignition on, 0.8-2.3 VDC Engine at idle, ECT > 70 °C voltage varies from 1.0-2.5 VDC Ignition off, approx. 10 Ohms	P/O M16/6 see also pins E.31-E.34
F.8	Main gound to W16/6	Approx. 0 Ohms to ground
F.13	Ignition coil 1 signal output	Ignition on 12 VDC Starter cranks > 10 VDC (voltage drops slightly during cranking)
F.15	Main gound to W16/6	Approx. 0 Ohms to ground
F.20	Ignition coil 2 signal output	Same as pin F.13