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Cat Man
Cat Man, Cat Engine Expert
Category: Medium and Heavy Trucks
Satisfied Customers: 8331
Experience:  I am ASE Master Truck Certified.
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I am working on a truck company whose employees changed the

Customer Question

I am working on a truck for a company whose employees changed the battery and hooked it up wrong and shorted out some things and the truck wouldn't run. I narrowed the problem down to the ecm. After replacing the ecm the truck started but will only run on the 3 injectors. Showing no codes.
Submitted: 3 months ago.
Category: Medium and Heavy Trucks
Expert:  Jeremy replied 3 months ago.

My name is ***** ***** I will assist you with your question today.

I'm an independent contractor and I don't get paid until a rating has been made.

We can go back and forth as needed to help resolve the issue you are having. Follow ups are free after ratings, so rate in confidence!

What is the year, make, model of the truck and what engine do you have?

It sounds like the ECM is not programmed to the truck, on the truck, after the ECM replacement. That needs to be done first.

After that and you are still running on only 3 injectors, then check the harness going into the ECM. Make sure it is clean and seated properly. If still good, the ECM you got is defective.


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Customer: replied 3 months ago.
1999 international c12
Expert:  Jeremy replied 3 months ago.

What engine? If the international engine, it needs to have the ECM programmed on the truck so the ESC and ECM software match. That still needs to be done first followed by a harness check. Also, check the IDM if International engine for it could be burned up which will cause the misfires.

Customer: replied 3 months ago.
Caterpillar c12 engine
Expert:  Jeremy replied 3 months ago.

CAT engine, let me opt out and get the Cat specialist for you.

He goes by Catman. He can give you exact pin point spots to check for the misfires on the engine.

Expert:  Cat Man replied 3 months ago.
Thanks for asking your question. I will try and help you out.
I would like to ask you a few questions first to better help me understand your situation.
So everything was working fine on the engine until the battery was connected backwards?
How can you tell it's running on three cylinders?
What service tool are you using to read the ECM? Is it Cat ET?

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