| All values measured to ground unless otherwise noted | |||
| N30/1 | |||
| 1 | Circuit 87 ABS fused power input from Overvoltage protection relay module | Ignition on 12 VDC | Feed from K20 via Z99/1 |
| 2 | 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 |
| 3 | Main ground to W16/4 | Approx. 0 Ohms to ground or measure to circuit 30 12 VDC |
same as pin 16 |
| 4 | Left rear axle hold valve signal, switched ground activates solenoid valve A7/3y10 | 12 VDC with valve energized 0 VDC with valve not energized |
coil res. approx. 5,4-12,6 Ohms |
| 5 | Return pump valve activation switched ground signal output | 12 VDC to pin 20 with relay activated | coil resistance approx. 40-80 Ohms |
| 6 | 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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| 7 | Pin not used | ||
| 8 | Solenoid valve relay activation switched ground signal output | 12 VDC to pin 20 with relay activated | coil resistance approx. 40-80 Ohms |
| 9 | ASR charging pump relay activation switched ground signal output | 12 VDC to pin 1 | max 60 sec. |
| 10 | 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 |
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| 11 | Pin not used | ||
| 12 | ASR malfunction signal output to lamp e22 | Ignition on < 2 VDC, indicator lamp on engine at idle 12 VDC, indicator lamp off |
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| 13 | ASR charging pump | Ignition on 12 VDC measure at connection "SP" approx. 1.8-11 bar |
max 60 sec. |
| 14 | Return pump relay activated monitoring signal input and pump voltage supply | 12 VDC to pin 20 with relay activated | coil resistance approx. 40-80 Ohms Note 2 |
| 15 | Pin not used | ||
| 16 | Main ground to W16/4 | Approx. 0 Ohms to ground or measure to circuit 30 12 VDC |
same as pin 3 |
| 17 | Left front axle hold valve signal, switched ground activates solenoid valve A7/3y6 | 12 VDC with valve energized 0 VDC with valve not energized |
coil res. approx. 5,4-12,6 Ohms |
| 18 | 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 |
| 19 | Pin not used | ||
| 20 | Voltage supply output to return pump and solenoid valve relay | Ignition on 12 VDC measure to pin 8 12 VDC with relay activated |
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| 21 | Pin not used | ||
| 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 |
coil res. approx. 5,4-12,6 Ohms |
| 23 | Switchover valve signal output, switched ground activates solenoid valve A7/3y5 | 12 VDC with valve energized 0 VDC with valve not energized |
coil res. approx. 5,4-12,6 Ohms |
| 24 | ABS MIL signal output to lamp e17 | Ignition on < 2 VDC, indicator lamp on engine at idle 12 VDC, indicator lamp off |
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| 25 | Pin not used | ||
| 26 | Stop lamp switch (normally closed) input | 12 VDC with brakes not applied, 0 VDC with brakes applied. | |
| 27 | ASR brake fluid level switch input | ||
| 28 | Parking brake switch signal input | Parking brake pedal depressed Ignition on 0 VDC |
also feeds indicator lamp A1e7 |
| 29 | Stop lamp switch (normally open) input. Same signal as to brake lights |
12 VDC with brakes applied, 0 VDC with brakes not applied | |
| 30 | "Diagnostic port" for DTC readout and diagnostic purpose | Ignition on 12 VDC | To be tested with HHT refer to D.M. |
| 31,32 | Pins not used | ||
| 33 | ASR snow chain mode indication signal output | Engine at idle, press and hold switch S76 to position on < 1 VDC, indicator lamp on position off 12 VDC indicator lamp off |
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| 34 | Inlet valve signal output, switched ground activates solenoid valve A7/3y15 | 12 VDC with valve energized 0 VDC with valve not energized |
coil res. approx. 5,4-12,6 Ohms |
| 35 | Pin not used | ||
| 36 | Right rear axle hold valve signal, switched ground activates solenoid valve A7/3y12 | 12 VDC with valve energized 0 VDC with valve not energized |
coil res. approx. 5,4-12,6 Ohms |
| 37 | Right rear axle release valve signal, switched ground activates solenoid valve A7/3y13 | 12 VDC with valve energized 0 VDC with valve not energized |
coil res. approx. 2,8-6,6 Ohms |
| 38 | 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 |
| 39 | Pin not used | ||
| 40 | Left rear axle release valve signal, switched ground activates solenoid valve A7/3y11 | 12 VDC with valve energized 0 VDC with valve not energized |
coil res. approx. 2,8-6,6 Ohms |
| 41 | Right front axle release valve signal, switched ground activates solenoid valve A7/3y9 | 12 VDC with valve energized 0 VDC with valve not energized |
coil res. approx. 2,8-6,6 Ohms |
| 42 43 |
Right rear axle VSS sensor, - input. Right rear axle VSS sensor, + input. |
ECM disconnected 0,6-3,2 kOhms across pins 42 and 43 Sine wave. Frequency varies with wheel speed. |
Note 1 |
| 44 45 |
Left rear axle VSS sensor, - input. Left rear axle VSS sensor, + input. |
ECM disconnected 0,6-3,2 kOhms across pins 44 and 45 Sine wave. Frequency varies with wheel speed. |
Note 1 |
| 46 47 |
RF VSS sensor, - input RF VSS sensor, + input |
ECM disconnected 0,8-3,7 kOhms across pins 46 and 47 Sine wave. Frequency varies with wheel speed |
Note 1 |
| 48 49 |
LF VSS sensor, - input LF VSS sensor, + input |
ECM disconnected 0,8-3,7 kOhms across pins 48 and 49 Sine wave. Frequency varies with wheel speed |
Note 1 |
| 50 | Pin not used | ||
| 51 | 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 |
| 53 | CAN-Bus (low side). high speed data transfer bus input and output, shares data with other ECMs | ||
| 52 | Pin not used | ||
| 54 | Left front axle release valve signal, switched ground activates solenoid valve A7/3y7 | 12 VDC with valve energized 0 VDC with valve not energized |
coil res. approx. 2,8-6,6 Ohms |
| 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. | |