hi moderators if you think this Reply should be moved please do so
Mark
hi mark, please could you show me how to connect the et directly to the ecm?? that would be really handy.
Hi mrappels,it is quite easy to power up an ECM via a different power source than the machine. there are a couple of things to be aware of
1- the ECMs will run on either 12v or 24 volt
2- even though multiple power supply's and returns are indicated on electrical schematics only one B+ and one B- is required to operate the ECM for test purposes
3- generally 5 wires are needed for the ECM to communicate with ET
B+, B-,key switch B+,CDL + and CDL -
4- be aware that on highway trucks use different diagnostic plugs than machine diagnostic plugs
5- Cat uses a number different ECM's and some even look the same but the connection pin outs are different
Here is a list of common ECM's
ADAM 2 - has two forty pin connectors used ,as engine ECM
MAC- has one or two forty pin connectors ,looks the same as ADEM 2 ECM, used as machine system ECM
ADEM 3- has two 70 pin connectors used as engine ECM
ABL- Has one or two seventy pin connectors, looks the same as ADEM 3 ECM, used as machine system ECM
ADEM 4- has one seventy pin connector and one,one hundred and twenty pin connector, used for engine and machine systems
ADEM A4-E2 Has two 64 pin connectors used as engine ECM on later common rail engines (Perkins/Mitsubishi)
for the ADEM 2 ECM pin outs
B+ to pin#4 also connect to diagnostic connector pin#A
B- to pin#5 also connect to diagnostic connector pin#B
CDL+ to pin#9 also connect to diagnostic connector pin#D (green)
CDL- to pin#3 also connect to diagnostic connector pin#E (brown)
switched input B+ to pin#6
For MAC ECM
B+ to pin#1 also connect to diagnostic connector pin#A
B- to pin#2 also connect to diagnostic connector pin#B
CDL+ to pin#9 also connect to diagnostic connector pin#D
CDL- to pin#3 also connect to diagnostic connector pin#E
switched input B+ to pin#40
For ADEM 3 and 4 ECM (engine)
B+ to either 48,52 or 53 also connect to diagnostic connector pin#A
B- to either 63,65 or 67 also connect to diagnostic connector pin#B
CD+L to pin#8 also connect to diagnostic connector pin#D
CD-L to pin#9 also connect to diagnostic connector pin#E
switched input B+ to pin #70
For ADEM 3 and 4 (machine)
B+ to pin#1 also connect to diagnostic connector pin#A
B- to pin #2 also connect to diagnostic connector pin#B
CDL+ to pin #8 also connect to diagnostic connector pin#D
CDL- to pin#7 also connect to diagnostic connector pin#E switched input B+ to pin #58
for A4 E2 ECM
B+ to pin#1,2,9 or 10 also connect to diagnostic connector pin#A
B- to pin #7,8,15 or 16 also connect to diagnostic connector pin#B
CDL+ to pin #23 also connect to diagnostic connector pin#D
CDL- to pi #24 also connect to diagnostic connector pin#E
switched input to pin#40
some cat part numbers that may be useful
diagnostic connector P# 8T8736
A3 ECM connector 160-7689
sockets for above 9x3402
A2 ECM connector 3E6286
A3 ABL ECM connector 160-7690
MAC ECM connector 101-0205
A4E2 ECM connector 245-1042
sockets for above 267-9572
here is some screen shots of ECM ET stand alone Data