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Q: What is an ECM-relay and where is it located?

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I want to know where the EMC relay or main relay is located on my truck? and can I replace it myself? I am very mechanically inclined, I just never dealt with this particular problem. also, my truck diagnostic test is showing P0052 OBO-II trouble code: H025, Heater Control Circuit high (Bank 2) sensor 1 what does this mean?

My car has 226000 miles.
My car has an automatic transmission.

Hey there. The ECM relay on this vehicle is called an auto shutdown relay and is located in the engine compartment integrated power module control box. The P0052 code you are getting is for the passenger side O2 sensor closest to the exhaust manifold heater circuit has open circuit or wires are damaged causing the open circuit.

Have the computer Check Engine Light checked and monitor the left and right O2 sensors heater circuit when you start the vehicle. You should see both sides to be at equal readings. Replace the passenger side O2 sensor and clear the codes. Then road test the vehicle while monitoring the O2 sensors and make sure no codes return and check engine light stays off. If you’re looking to have this done, a certified technician from YourMechanic can come to your car’s location to assist with repairs.

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