BAR AS 8G8977 - Caterpillar

Requirements For The ECM
The Electronic Control Module (ECM) for the Diesel Particulate Filter Monitor System is powered by either a +12 VDC or +24 VDC nominal battery. Refer to Table 1 for the limits for the voltage for the ECM. Refer to Illustration There is one 5 VDC +/-0.25 VDC at 500 mA auxiliary Power Supply on the ECM, routed to the machine pin group. A single return pin is used for this power supply. An "AD" channel monitors this power supply. The ECM internal power supply will provide +5 VDC for external sensor use. Refer to Illustration 1.
Illustration 1 g01340837
Illustration 2 displays mounting the Diesel Particulate Filter Monitor System to the ECM.
Illustration 2 g01340267
Table 1
Power Supply Requirements    
Requirements for 12 VDC or 24 VDC system     Value     Notes    
Operating Minimum Voltage     +9V     Minimum continuous operating voltage without damage to the ECM    
Operating Minimum Voltage     +32V     Maximum continuous operating voltage without damage to the ECM    
Overvoltage Maximum (two minutes continuous)     +80V     At 25 °C (77 °F)    
Reverse Voltage (one hours)     -32V    
85 °C (185 °F)    
power up voltage for the ECM     +9V     Minimum voltage for the ECM in order to run internally. Operating the engine at this voltage will cause damage to the ECM.    
Cranking Voltage            
Maximum current draw with key switch off     10mA        
Maximum current draw with 0 engine speed and no loads being driven     500mA        
Maximum continuous operating current draw     10A     This is highly dependent upon the number and type of loads driven by the ECM.    
Recommended Battery Fuse size     15A        Programming For The ECM
The ECM is flash programmed via the Customer Data Link (CDL) with the service tool.Key Switch For The ECM
The ECM Key Switch provides the ability to shut down the ECM via a low current switch. The ECM Key Switch also increases the life of the batteries by shutting the ECM off. The Key Switch also allows operators to remotely power off the ECM. The Key Switch controls when the ECM powers up. With the Key Switch "OFF", the ECM current draw will not exceed 10mA.Connector For The ECM
The ECM uses a 70 pin connector to connect to the OEM vehicle wiring harness. The ECM Connector Screw torque should be 6 1 N m (4 0.7 lb ft)Connector Wire Gauge Size For The ECM
The battery positive and negative connections must be made with 14 gauge SAE J1128 type GXL wire for the Deutsch stamped and formed terminal or the Deutsch solid terminal. All other connections may be16 gauge or 18 gauge SAE J1128 type SXL or 14, 16 or 18 gauge SAE J1128 type GXL (or equivalent wire).For most components on the engine an 18 gauge wire has sufficient current capacity, however, many applications will benefit from the increased reliability and durability of 16 gauge