Diagnostic Code P0540 continue to return and the MIL light is on?

This problem is noticed on
United States Chevrolet Silverado 2500 4X4 of year 2007 with  Engine: 6.6 Diesel model.

Car diagnostic code P0540 is related to Intake Air heat code.
In this case The  has been replaced.As you mentioned that this code comes up again,this clears that you have replace this module.If you have not replaced this intake air heater module then replace it.But if you have already replaced intake air heater module then , in that case check the resistance of the intake air heater on the passenger front top of the engine . This is the square shaped device with the battery cables on the top right side of the engine. Behind it goes to the top of the EGR valve.

Resistance of the intake air heater will be very low considering a 125 amp fuse feeds it.It will be better to test for resistance over the two parts and see if it is open.
What condition is the wiring in the small plug, and the terminals in that plug to plug into the intake air heater?
Test those back to the ECM? If any connection is loose or shorted then it can be the issue.

Also other thing to be checked is 125 amp mega fuse under the black box on the firewall behind the passenger side battery? Check If that fuse open?If yes then replace it.

Checking inspecting this possibilities will help you.

Thanks.

---------

See below list of more car diagnostic error code solution  :-----

Evaporative Emissions System codes details?

http://schematicsdiagram.blogspot.com/2011/11/evaporative-emissions-system-codes.html

 

Engine Misfire codes on Chevrolet Malibu?

http://schematicsdiagram.blogspot.com/2011/12/engine-misfire-codes-on-chevrolet.html

Misfire on cylinder 4?

http://schematicsdiagram.blogspot.com/2011/12/misfire-on-cylinder-4.html

ABS trouble codes for all 1994-00 Acura models?

http://repairhelpcenter.blogspot.com/2011/11/abs-trouble-codes-for-all-1994-00-acura.html

Diagnostic code P0010?

http://schematicsdiagram.blogspot.com/2011/12/diagnostic-code-p0010.html

Diagnostic Code P1396?

http://howtobyme.blogspot.com/2011/11/diagnostic-code-p1396.html

Code P0452?

http://howtobyme.blogspot.com/2011/11/code-p0452.html

OBD code P0172 on Buick Park Avenue?

http://howtobyme.blogspot.com/2011/11/obd-code-p0172-on-buick-park-avenue.html

DTC Code P0321 on Buick Park Avenue?

http://howtobyme.blogspot.com/2011/11/dtc-code-p0321-on-buick-park-avenue.html

Error Code P0471 on 2007 Dodge Ram 3500?

http://howtobyme.blogspot.com/2011/11/error-code-p0471-on-2007-dodge-ram-3500.html

P0304 Error code on Dodge Neon?

http://howtobyme.blogspot.com/2011/11/p0304-error-code-on-dodge-neon.html

OBDII scan is receiving NO BUS CODE?

http://howtobyme.blogspot.com/2011/11/obdii-scan-is-receiving-no-bus-code.html

How to Clear OBD error Codes on Acura Car Models?

http://repairhelpcenter.blogspot.com/2011/11/how-to-clear-obd-error-codes-on-acura.html

Diagnosis and Testing Car Components?

http://vwrepairhelp.blogspot.com/2011/11/diagnosis-and-testing-car-components.html

Diagnostic Trouble Codes list for Acura Car Models?

Part 1.

http://repairhelpcenter.blogspot.com/2011/11/diagnostic-trouble-codes-list-for-acura_18.html

Diagnostic Trouble Codes list for Acura Car Models?

Part 2.

http://repairhelpcenter.blogspot.com/2011/11/diagnostic-trouble-codes-list-for-acura.html

Diagnostic Code 43 and 71 on 1991 Toyota Pickup?

http://schematicsdiagram.blogspot.com/2011/12/diagnostic-code-43-and-71-on-1991.html

Code P0132 On Acura TL?

http://schematicsdiagram.blogspot.com/2011/12/code-p0132-on-acura-tl.html

P0031 code on Dodge Dakota?

http://schematicsdiagram.blogspot.com/2011/12/p0031-code-on-dodge-dakota.html

How to get diagnostic Code without OBD Scanner on Pre 1995 Toyota Pickup?

http://schematicsdiagram.blogspot.com/2011/12/how-to-get-diagnostic-code-without-obd.html

OBD-II Trouble Code P0300?

http://schematicsdiagram.blogspot.com/2011/12/obd-ii-trouble-code-p0300.html

Getting diagnostic code P0016?

http://schematicsdiagram.blogspot.com/2011/12/getting-diagnostic-code-p0016.html

How to Read Codes from Check Engine Light?

http://schematicsdiagram.blogspot.com/2011/12/how-to-read-codes-from-check-engine.html

Bank 2 Sensor 1 Heater circuit Failure?

You get check engine light on dash.In this case Engine computer module called ECM has to be scanned.
In scanning you get error code P0155.
This error code means.Bank 2 Sensor 1 heater failure.
This refers to the heater inside one of your oxygen sensors. The computer is not reading current to the heater. The problem may be the wires or the sensor itself. The thing to do is to check for voltage at the sensor connector with the key turned on. This particular sensor is right on the front of the engine by the radiator. If the voltage is there, the sensor is probably bad. You can also test the sensor heater with an ohmmeter as follows:
Testing Heating Element
Before Testing any electrical component, inspect the wiring and connectors for damage. Also wiggle the connectors to ensure a that they are firmly engaged.
Disconnect the electrical harness from each of the sensors.
The white wires in the sensor connector are the power and ground circuits for the heater.
Connect the ohmmeter test leads to the terminals of the white wires in the heated oxygen sensor connector.
Check the resistance of the sensor, if it is not within 4-7 ohms, replace the sensor.
The picture below is the sensor on bank 1, by the firewall. The one you want (bank 2, sensor 1) is on the front of the engine.

See the Sample diagram shown below :----

This details will help you.

----------

If you need dis-assembly or replacement instructions for any other auto/car part, or you want to ask question related to your car/truck jeep problem then please leave the comment with your details, so I can provide you the required instructions and solutions.

For more Car error code related solutions,see the list below:----

Engine Misfire codes on Chevrolet Malibu?

http://schematicsdiagram.blogspot.com/2011/12/engine-misfire-codes-on-chevrolet.html

ABS trouble codes for all 1994-00 Acura models?

http://repairhelpcenter.blogspot.com/2011/11/abs-trouble-codes-for-all-1994-00-acura.html

Diagnostic code P0010?

http://schematicsdiagram.blogspot.com/2011/12/diagnostic-code-p0010.html

Diagnostic Code P1396?

http://howtobyme.blogspot.com/2011/11/diagnostic-code-p1396.html

Code P0452?

http://howtobyme.blogspot.com/2011/11/code-p0452.html

OBD code P0172 on Buick Park Avenue?

http://howtobyme.blogspot.com/2011/11/obd-code-p0172-on-buick-park-avenue.html

DTC Code P0321 on Buick Park Avenue?

http://howtobyme.blogspot.com/2011/11/dtc-code-p0321-on-buick-park-avenue.html

Error Code P0471 on 2007 Dodge Ram 3500?

http://howtobyme.blogspot.com/2011/11/error-code-p0471-on-2007-dodge-ram-3500.html

P0304 Error code on Dodge Neon?

http://howtobyme.blogspot.com/2011/11/p0304-error-code-on-dodge-neon.html

OBDII scan is receiving NO BUS CODE?

http://howtobyme.blogspot.com/2011/11/obdii-scan-is-receiving-no-bus-code.html

How to Clear OBD error Codes on Acura Car Models?

http://repairhelpcenter.blogspot.com/2011/11/how-to-clear-obd-error-codes-on-acura.html

Diagnosis and Testing Car Components?

http://vwrepairhelp.blogspot.com/2011/11/diagnosis-and-testing-car-components.html

Diagnostic Trouble Codes list for Acura Car Models?

Part 1.

http://repairhelpcenter.blogspot.com/2011/11/diagnostic-trouble-codes-list-for-acura_18.html

Diagnostic Trouble Codes list for Acura Car Models?

Part 2.

http://repairhelpcenter.blogspot.com/2011/11/diagnostic-trouble-codes-list-for-acura.html

Diagnostic Code 43 and 71 on 1991 Toyota Pickup?

http://schematicsdiagram.blogspot.com/2011/12/diagnostic-code-43-and-71-on-1991.html

Code P0132 On Acura TL?

http://schematicsdiagram.blogspot.com/2011/12/code-p0132-on-acura-tl.html

P0031 code on Dodge Dakota?

http://schematicsdiagram.blogspot.com/2011/12/p0031-code-on-dodge-dakota.html

How to get diagnostic Code without OBD Scanner on Pre 1995 Toyota Pickup?

http://schematicsdiagram.blogspot.com/2011/12/how-to-get-diagnostic-code-without-obd.html

OBD-II Trouble Code P0300?

http://schematicsdiagram.blogspot.com/2011/12/obd-ii-trouble-code-p0300.html

Diagnostic code P0010?

The Diagnostic code shown in car scanning.When check engine light comes up on engine,the The ecm has to be scanned.
If you are getting error code P0010.
Code P0010 refers to a fault at the Intake Camshaft Position (CMP) Actuator Solenoid Control Circuit Bank 1. This code will set if the ECM (Engine Control Module) detects that the commanded state of the driver and the actual state of the control circuit do not match for greater than 3 s.
The service procedure requires close monitoring with a scan tool. Well it may be too technical for you, but simply put, it may require replacing the CMP actuator solenoid valve if it fails the component test. If the component is found to be okay, the circuit and wirings should be checked for possible shorts or open, and also the signal performance. If all circuit tests proved normal, a replacement ECM may be recommended.
If the engine light and code is consistently present, most likely it's the actuator solenoid valve. Check it out with your trusted mechanic. 

This details will help you.

----------

If you need dis-assembly or replacement instructions for any other auto/car part, or you want to ask question related to your car/truck jeep problem then please leave the comment with your details, so I can provide you the required instructions and solutions.

Diagnostic Code

Diagnostic Code P1396?

http://howtobyme.blogspot.com/2011/11/diagnostic-code-p1396.html

Code P0452?

http://howtobyme.blogspot.com/2011/11/code-p0452.html

OBD code P0172 on Buick Park Avenue?

http://howtobyme.blogspot.com/2011/11/obd-code-p0172-on-buick-park-avenue.html

DTC Code P0321 on Buick Park Avenue?

http://howtobyme.blogspot.com/2011/11/dtc-code-p0321-on-buick-park-avenue.html

Error Code P0471 on 2007 Dodge Ram 3500?

http://howtobyme.blogspot.com/2011/11/error-code-p0471-on-2007-dodge-ram-3500.html

P0304 Error code on Dodge Neon?

http://howtobyme.blogspot.com/2011/11/p0304-error-code-on-dodge-neon.html

OBDII scan is receiving NO BUS CODE?

http://howtobyme.blogspot.com/2011/11/obdii-scan-is-receiving-no-bus-code.html

How to Clear OBD error Codes on Acura Car Models?

http://repairhelpcenter.blogspot.com/2011/11/how-to-clear-obd-error-codes-on-acura.html

Diagnosis and Testing Car Components?

http://vwrepairhelp.blogspot.com/2011/11/diagnosis-and-testing-car-components.html

Diagnostic Trouble Codes list for Acura Car Models?

Part 1.

http://repairhelpcenter.blogspot.com/2011/11/diagnostic-trouble-codes-list-for-acura_18.html

Diagnostic Trouble Codes list for Acura Car Models?

Part 2.

http://repairhelpcenter.blogspot.com/2011/11/diagnostic-trouble-codes-list-for-acura.html

Diagnostic Code 43 and 71 on 1991 Toyota Pickup?

http://schematicsdiagram.blogspot.com/2011/12/diagnostic-code-43-and-71-on-1991.html

Code P0132 On Acura TL?

http://schematicsdiagram.blogspot.com/2011/12/code-p0132-on-acura-tl.html

P0031 code on Dodge Dakota?

http://schematicsdiagram.blogspot.com/2011/12/p0031-code-on-dodge-dakota.html

How to get diagnostic Code without OBD Scanner on Pre 1995 Toyota Pickup?

http://schematicsdiagram.blogspot.com/2011/12/how-to-get-diagnostic-code-without-obd.html

Engine Misfire codes on Chevrolet Malibu?

http://schematicsdiagram.blogspot.com/2011/12/engine-misfire-codes-on-chevrolet.html

ABS trouble codes for all 1994-00 Acura models?

http://repairhelpcenter.blogspot.com/2011/11/abs-trouble-codes-for-all-1994-00-acura.html

Code P0132 On Acura TL?

DTC P0132 - O2 Oxygen Sensor Circuit High Voltage (Bank1, Sensor1)
This involves the front oxygen sensor on Bank 1. This code indicates that the heated oxygen sensor reading is too high. It  indicates the voltage at the sensor is over 1.5 volts.

A code P0132 may mean that one or more of the following has happened:
The oxygen sensor heater circuit is shorted out
The wiring to the sensor is broken / frayed (less likely).

Oxygen sensor circuit issues. Check wiring for possible melted insulation or bad connection at connector.If wiring looks good run tests to diagnose. Sensor one, bank one is below the exhaust manifold on the passenger side of the engine.

TESTING4-WIRE SENSOR
4-wire sensors are HO2 sensors.
On 4-wire sensors, one of the connector terminals is the SOUT, one of the terminals is the SGND, one of the terminals is the HPWR and the other is the HGND. To identify the 4 terminals, perform the following:

1. Locate the O2 sensor (#2 in pic below) and its pigtail connector. It may be necessary to raise and safely support the vehicle to gain access to the connector.

1. Disengage the sensor pigtail connector from the vehicle harness connector.
2. Using a DVOM set to read 12 volts, attach the DVOM ground lead to a good engine ground.
3. Have an assistant turn the ignition switch ON without actually starting the engine.
4. Probe all 4 terminals in the vehicle harness connector. One of the terminals should exhibit 12 volts of power with the ignition key ON; this is the HPWR terminal.
   1. If the HPWR terminal was identified, note which of the sensor harness connector terminals is the HPWR, then match the vehicle harness connector to the sensor pigtail connector. Label the corresponding sensor pigtail connector terminal with HPWR.
   2. If none of the terminals showed 12 volts of power, locate and test the heater relay or fuse. Then, perform Steps 2-6 again.

1. Have your assistant turn the ignition OFF
2. Using the DVOM set to measure resistance (ohms), attach one of the leads to the HPWR terminal of the sensor pigtail connector. Use the other lead to probe the 3 remaining terminals of the sensor pigtail connector, one at a time. The DVOM should show continuity with only one of the remaining unidentified terminals; this is the HGND terminal.
   1. If continuity was found with only 1 of the 2 unidentified terminals, label the HGND terminal on the sensor pigtail connector.
   2. If no continuity was evident, or if continuity was evident from all unidentified terminals, the O2 sensor is defective.
   3. If continuity was found at 2 of the other terminals, the sensor is probably defective. However, the sensor may not necessarily be defective, because it may have been designed with the 2 ground wires joined inside the sensor in case one of the ground wires is damaged; the other circuit could still function properly. Though, this is highly unlikely. A wiring diagram is necessary in this particular case to know whether the sensor was so designed.

Reattach the sensor pigtail connector to the vehicle harness connector. Start the engine and allow it to warm up to normal operating temperature, then turn the engine OFF. Using a DVOM set to read 100-900 mV (millivolts) DC, backprobe the negative DVOM lead to one of the unidentified terminals and the positive lead to the other unidentified terminal. 

CAUTION While the engine is running, keep clear of all moving and hot components. Do not wear loose clothing. Otherwise severe personal injury or death may occur. 

1. Have an assistant restart the engine and allow it to idle.
2. Check the DVOM for voltage.
   1. If no voltage is evident, check your DVOM leads to ensure that they are properly connected to the terminals. If still no voltage is evident at either of the terminals, either the terminals were accidentally marked incorrectly or the sensor is defective.
   2. If voltage is present, but the polarity is reversed (the DVOM will show a negative voltage amount), turn the engine OFF and swap the 2 DVOM leads on the terminals. Start the engine and ensure that the voltage now shows the proper polarity.
   3. If voltage is evident and is the proper polarity, the positive DVOM lead is attached to the SOUT and the negative lead to the SGND terminals.

1. Have your assistant turn the engine OFF.
2. Label the sensor pigtail SOUT and SGND terminals.

REMOVAL and INSTALLATION
WARNING The sensors use a pigtail and connector. This pigtail should not be removed from the sensor. Damage or removal of the pigtail or connector could affect proper operation of the oxygen sensor. Keep the electrical connector and louvered end of the sensor clean and free of grease. NEVER use cleaning solvents of any type on the sensor! The sensor may be difficult to remove when the engine temperature is below 120°F (48°C). Excessive removal force may damage the threads in the exhaust manifold or pipe; follow the removal procedure carefully. 

1. Make sure the ignition is OFF, then disconnect the negative battery cable.
2. Locate the oxygen sensor. It protrudes from the exhaust manifold or exhaust pipe (it looks somewhat like a spark plug). It may be necessary to raise and safely support the vehicle to access the sensor.
3. Unplug the sensor electrical connector.

Fig. Fig. 5: Loosen the oxygen sensor using a wrench as shown, or use a sensor socket made especially for that purpose

1. Carefully unscrew the sensor, then remove the oxygen sensor from the manifold or pipe.

To install:

1. During and after the removal, be very careful to protect the tip of the sensor if it is to be reused. Do not let it to come in contact with fluids or dirt. Do not clean it or wash it.
2. Apply a coat of anti-seize compound to the bolt threads but DO NOT allow any to get on the tip of the sensor.
3. Install the sensor in the manifold or exhaust pipe.
4. Attach the electrical connector and ensure a clean, tight connection.
5. If raised, carefully lower the vehicle.
6. Connect the negative battery cable.

This details should help.Thanks.

-----------------------------

If you need dis-assembly or replacement instructions for any other auto/car part, or you want to ask question related to your car/truck jeep problem then please leave the comment with your details, so I can provide you the required instructions and solutions.

For more Car OBD Code details and solutions,see the list shown below:---------

Diagnostic Code P1396?

http://howtobyme.blogspot.com/2011/11/diagnostic-code-p1396.html

Code P0452?

http://howtobyme.blogspot.com/2011/11/code-p0452.html

OBD code P0172 on Buick Park Avenue?

http://howtobyme.blogspot.com/2011/11/obd-code-p0172-on-buick-park-avenue.html

DTC Code P0321 on Buick Park Avenue?

http://howtobyme.blogspot.com/2011/11/dtc-code-p0321-on-buick-park-avenue.html

Error Code P0471 on 2007 Dodge Ram 3500?

http://howtobyme.blogspot.com/2011/11/error-code-p0471-on-2007-dodge-ram-3500.html

P0304 Error code on Dodge Neon?

http://howtobyme.blogspot.com/2011/11/p0304-error-code-on-dodge-neon.html

OBDII scan is receiving NO BUS CODE?

http://howtobyme.blogspot.com/2011/11/obdii-scan-is-receiving-no-bus-code.html

How to Clear OBD error Codes on Acura Car Models?

http://repairhelpcenter.blogspot.com/2011/11/how-to-clear-obd-error-codes-on-acura.html

Diagnosis and Testing Car Components?

http://vwrepairhelp.blogspot.com/2011/11/diagnosis-and-testing-car-components.html

Diagnostic Trouble Codes list for Acura Car Models?

Part 1.

http://repairhelpcenter.blogspot.com/2011/11/diagnostic-trouble-codes-list-for-acura_18.html

Diagnostic Trouble Codes list for Acura Car Models?

Part 2.

http://repairhelpcenter.blogspot.com/2011/11/diagnostic-trouble-codes-list-for-acura.html

Diagnostic Code 43 and 71 on 1991 Toyota Pickup?

http://schematicsdiagram.blogspot.com/2011/12/diagnostic-code-43-and-71-on-1991.html