All values measured to ground unless otherwise noted
Conn./Plug/Pin Pin Information Test Value Comments
N54      
1 Interior mirror locking confirmation signal output Using IR transmitter, lock at interior mirror,
Red indicator flashes. Use scope 12 Vpp when confirmation occurs
 
2 Interior mirror unlocking confirmation signal output Using IR transmitter, unlock at interior mirror,
Green indicator flashes. Use scope 12 Vpp when confirmation occurs
 
3 Driver side locking confirmation signal output Using IR transmitter, lock at driver side,
Red indicator flashes. Use scope 12 Vpp when confirmation occurs
 
4 Trunk infrared sensor signal input Using IR transmitter, lock at trunk, keep button depressed, monitor voltage. release button, voltage will raise approx. 0.4 VDC  
5 Trunk lid IR receiver voltage supply output 12 VDC at all times same as pin 12
1.6-7 Pins not used    
8 Interior mirror door infrared sensor signal input Using IR transmitter, lock at interior mirror, keep button depressed, monitor voltage. release button, voltage will raise approx. 0.4 VDC  
9 Circuit 30 main power input 12 VDC at all times Feed from F1f27
10 Driver side unlocking confirmation signal output Using IR transmitter, unlock at driver side,
Green indicator flashes. Use scope 12 Vpp when confirmation occurs
 
11 Unlock command SN1 signal output
Use remote control
Lock vehicle 12 VDC
Unlock vehicle < 1 VDC
 
12 Left front door IR receiver voltage supply output 12 VDC at all times same as pin 5
13 Sensor ground signal output Approx. 0 Ohms to ground same as pin 24
14 Circuit 15 main power input Ignition on 12 VDC Feed from F1f23
1.15-17 Pins not used    
18 Left front door infrared sensor signal input Using IR transmitter, lock at driver side, keep button depressed, monitor voltage. release button, voltage will raise approx. 0.4 VDC  
19 DTC diagnostic output. Also input for HHT data and tests. Ignition on approx. 10-14 VDC  
20 Trunk unlocking confirmation signal output Using IR transmitter, unlock at trunk,
Green indicator flashes. Use scope 12 Vpp when confirmation occurs
 
21 Trunk locking confirmation signal output Using IR transmitter, lock at trunk,
Red indicator flashes. Use scope 12 Vpp when confirmation occurs
 
22 Pin not used    
23 Lock command SN2 signal output
to PSE system
Use remote control
Unlock vehicle 12 VDC
Lock vehicle < 1 VDC
 
24 Sensor ground signal output Approx. 0 Ohms to ground same as pin 13
1.25-26 Pins not used    
27 Main ground to W7 Approx. 0 Ohms to ground  
N54/1      
1.1 Main ground to W19 Approx. 0 Ohms to ground  
1.2 Sensor ground signal output Approx. 0 Ohms to ground  
1.3 Unlock command SN1 signal ouput, generated from RCL system, to activate PSE module Use remote control
Lock vehicle 12 VDC
Unlock vehicle < 1 VDC
Initialized with IR transmitter or manually with key
1.4 Lock command SN2 signal output, generated from RCL system, to activate PSE module Use remote control
Unlock vehicle 12 VDC
Lock vehicle < 1 VDC
Initialized with IR transmitter or manually with key
1.5-7 Pins not used    
1.8 Unlock command driver side / trunk signal input Disconnect A37 plugs,
in quiescent condition > 20 kOhms
in unlock mode <40 Ohms
Initialized from
S87/1 and S88/2
or IR transmitter
1.9 Circuit 15 main power input Ignition on 12 VDC Feed from F1f23
1.10 Lock command driver side / trunk signal input Disconnect A37 plugs,
in quiescent condition > 20 kOhms
in unlock mode <60 Ohms
Initialized from
S87/1 and S88/2
or IR transmitter
1.11 Interior mirror IR receiver voltage supply output 5 VDC at all times  
1.12 Circuit 30 main power input 12 VDC at all times Feed from F1f27
1.13-18 Pins not used    
2.2 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.
Also other ECMs can cause CAN-Bus DTCs.
2.1 CAN-Bus (low side). High speed data transfer bus input and output, shares data with other ECMs. Disconnect plug 2 from N54/1. Approx. 120 Ohms across pins 2.H and 2.L HHT is also used for
CAN diagnosis
3.1 Transponder coil activation signal output and
ignition key ID code signal input
ECM disconnected, ignition on ,
use scope or storage DMM, measure to pin 3.2
approx. 125 kHz cycle, duration 0.2-0.8 sec.
 
3.2 Transponder coil signal low side output, shield    
Note For further tests, especially pneumatic system, refer to DM Body and Accessories HHT is also used for diagnosis.
Refer to DM Body and Accessories