| All values measured to ground unless otherwise noted | |||
| N47-1 | |||
| 1.1 | 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. |
HHT is also used for CAN diagnosis |
| 1.3 | CAN-Bus (low side). high speed data transfer bus input and output, shares data with other ECMs | ||
| 1.2 | Pin not used | ||
| 1.4 | Parking brake switch signal input | Parking brake pedal depressed Ignition on 0 VDC |
also feeds indicator lamp A1e7 |
| 1.5 | ASR OFF/ON recognition voltage coded signal input | Ignition on 5 VDC. ASR switch held in ON pos: 1 - 2 VDC Release switch: 3,3 - 6 VDC ASR switch held in OFF pos: < 1 VDC |
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| 1.6 | Pin not used | ||
| 1.7 | Stop lamp switch (normally closed) input | 12 VDC with brakes not applied, 0 VDC with brakes applied. | |
| 1.8,9 | Pins not used | ||
| 1.10 | "Diagnostic port" for DTC readout and diagnostic purpose | Ignition on 12 VDC | To be tested with HHT refer to D.M. |
| 1.11 | Pin not used | ||
| 1.12 1.13 |
Left rear axle VSS sensor, - input. Left rear axle VSS sensor, + input. |
ECM disconnected 0,6-3,2 kOhms across pins 1.12 and 1.13 Sine wave. Frequency varies with wheel speed. |
Note 1 |
| 1.14 1.15 |
Right rear axle VSS sensor, - input. Right rear axle VSS sensor, + input. |
ECM disconnected 0,6-3,2 kOhms across pins 1.14 and 1.15 Sine wave. Frequency varies with wheel speed. |
Note 1 |
| 1.16 | Main ground to W16/4 | Approx. 0 Ohms to ground or measure to circuit 30 12 VDC |
see also pin 1.34 |
| 1.17 | ABS MIL signal output to lamp e17 | Ignition on < 2 VDC, indicator lamp on engine at idle 12 VDC, indicator lamp off |
|
| 1.18 | Left rear axle VSS output, generated by L6/3, processed in ECM and sent to other ECMs | Ignition on, lift rear of vehicle. Turn left rear wheel > 1 rev/sec by hand > 3 VAC or with vehicle moving |
20 mph / 200 Hz 35 mph / 330 Hz square wave Feed to X62/13 |
| 1.19 | ASR warning signal output to lamp e21 | Measure to pin 1.27 Ignition on 12 VDC, indicator lamp on engine at idle < 2 VDC, indicator lamp off |
|
| 1.20,21 | Pins not used | ||
| 1.22 | Stop lamp switch (normally open) input. Same signal as to brake lights |
12 VDC with brakes applied, 0 VDC with brakes not applied | |
| 1.25 | Circuit 61 (engine running) signal input processed in IC from circuit D+ |
Ignition on < 1 VDC engine at idle 12 VDC |
D+ signal from generator G2 |
| 1.26 | LF VSS output, generated by L6/1, processed in ECM and sent to other ECMs | Ignition on, lift front of vehicle. Turn left front wheel > 1 rev/sec by hand > 3 VAC or with vehicle moving |
20 mph / 200 Hz 35 mph / 330 Hz square wave Feed to X62/12 |
| 1.27 | Circuit 87 ASR fused power input from BM | Ignition on 12 VDC | Feed from K1 |
| 1.33 | ASR malfunction signal output to lamp e22 | Ignition on < 2 VDC, indicator lamp on engine at idle 12 VDC, indicator lamp off |
|
| 1.34 | Main ground to W16/4 | Approx. 0 Ohms to ground or measure to circuit 30 12 VDC |
see also pin 1.16 |
| 2.1 | LF VSS sensor, + input | ECM disconnected 0,8-3,7 kOhms across pins 10 and 30 Sine wave. Frequency varies with wheel speed |
Note 1 |
| 2.2 | RF VSS sensor, + input | ECM disconnected 0,8-3,7 kOhms across pins 13 and 34 Sine wave. Frequency varies with wheel speed |
Note 1 |
| 2.3 | Solenoid valve relay activation switched ground signal output | 12 VDC to pin 2.17 with relay activated | coil resistance approx. 40-80 Ohms |
| 2.6 | Inlet valve signal output, switched ground activates solenoid valve A7/3y15 | 12 VDC with valve energized 0 VDC with valve not energized ECM disconnected 5.4-12.6 Ohms to ground |
|
| 2.7 | Left front axle hold valve signal, switched ground activates solenoid valve A7/3y6 | 12 VDC with valve energized 0 VDC with valve not energized ECM disconnected 5.4-12.6 Ohms to ground |
|
| 2.8 | Right front axle release valve signal, switched ground activates solenoid valve A7/3y9 | 12 VDC with valve energized 0 VDC with valve not energized ECM disconnected 2.8-6.6 Ohms to ground |
|
| 2.10 | Switchover valve signal output, switched ground activates solenoid valve A7/3y5 |
12 VDC with valve energized 0 VDC with valve not energized ECM disconnected 5.4-12.6 Ohms to ground |
|
| 2.12 | Left rear axle release valve signal, switched ground activates solenoid valve A7/3y11 | 12 VDC with valve energized 0 VDC with valve not energized ECM disconnected 2.8-6.6 Ohms to ground |
|
| 2.13 | Right rear axle hold valve signal, switched ground activates solenoid valve A7/3y12 | 12 VDC with valve energized 0 VDC with valve not energized ECM disconnected 5.4-12.6 Ohms to ground |
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| 2.14 | LF VSS sensor, - input | same as pin 2.1 | Note 1 |
| 2.15 | RF VSS sensor, - input | same as pin 2.2 | Note 1 |
| 2.17 | Voltage supply output to return pump and solenoid valve relay | Ignition on 12 VDC measure to pin 2.3 12 VDC with relay activated |
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| 2.20 | Left front axle release valve signal, switched ground activates solenoid valve A7/3y7 | 12 VDC with valve energized 0 VDC with valve not energized ECM disconnected 2.8-6.6 Ohms to ground |
|
| 2.22 | Right front axle hold valve signal, switched ground activates solenoid valve A7/3y8 | 12 VDC with valve energized 0 VDC with valve not energized ECM disconnected 5.4-12.6 Ohms to ground |
|
| 2.23 | Return pump valve activation switched ground signal output | 12 VDC to pin 2.17 with relay activated | coil resistance approx. 40-80 Ohms |
| 2.25 | Return pump relay activated monitoring signal input and pump voltage supply | 12 VDC to pin 2.17 with relay activated | coil resistance approx. 40-80 Ohms Note 2 |
| 2.26 | Left rear axle hold valve signal, switched ground activates solenoid valve A7/3y10 | 12 VDC with valve energized 0 VDC with valve not energized ECM disconnected 5.4-12.6 Ohms to ground |
|
| 2.27 | Right rear axle release valve signal, switched ground activates solenoid valve A7/3y13 | 12 VDC with valve energized 0 VDC with valve not energized ECM disconnected 2.8-6.6 Ohms to ground |
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| Note 1 | To test, spin wheel at 1 rev/sec, measure at least 120 mVAC between both wires of sensor. If voltage is OK, measure the sensor's resistance while pulling, twisting and bending the sensor wires, looking for intermittent opens. Finally, check the sensor tip and rotor teeth for dirt or breakage. An oscilloscope can also be used to check the waveform - chipped or dirty teeth show up as missing or malformed waves. | ||
| Note 2 | Engine at idle pressure increases quickly to 50-110 bar, then slowly up to 150-200 bar at connection "SP" |
max. charging time 60 sec. | |