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roybelding, Shop Foreman Freightliner trucks
Category: Medium and Heavy Trucks
Satisfied Customers: 5294
Experience:  Shop Froeman for Freightliner Trucks
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I have an 07 freightliner Columbia with a 60 series Detroit.

Customer Question

I have an 07 freightliner Columbia with a 60 series Detroit. It randomly will derate. Oil psi and water temp gauge go to 0 check engine light comes on, fan comes on and I lose power. I have replaced the oil psi sensor and the sensor harness. Still doing it. There is no pattern. Sometimes it goes a couple days between derates and sometimes only a couple miles. Usually if I keep driving it'll go back to running normal
Submitted: 1 year ago.
Category: Medium and Heavy Trucks
Expert:  spankyjr1 replied 1 year ago.

Good morning, sorry for delay, my name is ***** ***** you for asking your question, I will try and help you out.

Check all your pass through connections on firewall for damage and corrosion. Particularly from ecm to cab harness.

Those signals you are losing come from engine ecm and go into cab for gages,once you loose communication with dash light comes on you loose power and fan comes on for any safety related item, in this case it does not know how hot engine is so default setting turns fan on.

This is a common intermittent problem with no rhyme or reason, I have seen this dozens of times.

Use a good electrical cleaner to remove corrosion and electrical grease on connections to prevent future issues.

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Expert:  spankyjr1 replied 1 year ago.

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Customer: replied 1 year ago.
I have checked all those wires and still has the problem
Expert:  roybelding replied 1 year ago.

good morning my name is ***** ***** I will assist

what was the code for the check engine light???

I would check the harness from the drivers side of the block that wraps around the back of the motor and comes to the v pod, oil pressure switch and ehr is you have one.


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