Re installing ecm says connect batteries first?

[The motor guy]

What's wrong with installing the ecm, plugging it in and then hookup the batteries? I say batteries because this truck has two.

 

[The motor guy]

I just always thought things like this should be done with the batteries disconnected.

 

[researcher]

personally.. I wouldn't apply electricity to the circuit unless the computer was already connected. At least if you screw up connecting the battery the main ecu/ecm fuse would blow first! And protect the ecu! What vehicle is this?

 

[The motor guy]

personally.. I wouldn't apply electricity to the circuit unless the computer was already connected. At least if you screw up connecting the battery the main ecu/ecm fuse would blow first! And protect the ecu! What vehicle is this?

I agree. When I unplugged it it had an Allen head bolt that I loosened and that actually pulled the plug out at the same time.

 

[The motor guy]

I agree. When I unplugged it it had an Allen head bolt that I loosened and that actually pulled the plug out at the same time.

I guess that means I have to manually push it all the way in myself then screw the little Allen bolt back in.

 

[researcher]

I guess that means I have to manually push it all the way in myself then screw the little Allen bolt back in.

oh sorry I didn't know you were asking a question before.. sounds like the allen (hex) head is holding the ecm's plugs in place? If that's the case, then yup, manually push the connector in, line up the hole, screw it in..

 

[researcher]

What make/model is this ecm for? Just wondering..

 

[The motor guy]

What make/model is this ecm for? Just wondering

My dodge cummins. I'll have to look at the plug. I think only the ecm side is threaded, so I may need to use that bolt to jack the plug back in place too. The bolt never came out when I turned it to remove the plug. It stayed with the plug on the engine harness

 

[researcher]

ahh.. makes sense that it's not just an average Toyota Camry.. Connectors that are screwed/bolted in usually see a severe life (think tractors, earth movers), cummins brand now makes sense, they're going back to their industrial roots. so it's a captive bolt/screw, ya it's just there to hold it in place, it might not have a clip like a Toyota Camry ecm plug.

 

[The motor guy]

No, it does more than just hold it in. It unplugs it too. That's what I thought too, but I didn't even have to pull the plug.