Engine Error Codes

[Lowndex]

Is there a troubleshooting guide to debugging OBD-2 error codes? I found stuff on the net stating the description and association for error codes, but not troubling shooting approach.

https://www.engine-light-help.com/mercury-check-engine-light.html

http://www.troublecodes.net/mercury/grand-marquis-marauder-monterey-mountaineer-sable-2000-08/

[martyo]

What codes?

What vehicle?

[Lowndex]

I am seeking a diagnostic tree guide (causes and troubleshooting steps). I was hoping there is a comprehensive guide for say, the most common error codes. Else, I must piece together the information one code at a time.

Example for P0622 - means that the powertrain control module (PCM) has detected a malfunction with the generator field coil control circuit.


Causes for this code may include:
Faulty PCM PCM programming error Open or shorted generator field control circuit Defective alternator/generator


Troubleshooting Steps:
- Use the battery/alternator tester to load-test the battery and make sure that it is sufficiently charged. If it is not, charge the battery as recommended and test the alternator/generator. Follow manufacturer’s recommended specifications for minimum and maximum voltage output requirements for the battery and alternator.

- If the alternator/generator is not charging, proceed to the next step in your diagnosis. Use your source of vehicle information to obtain connector face views, connector pin-out charts, component locators, wiring diagrams, and diagnostic flow charts related to the code and vehicle in question.

- Check to see if there is battery voltage on the alternator/generator field control circuit by using the appropriate wiring diagram and your DVOM. If not check system fuses and relays and replace defective parts as required.

- If voltage is discovered at the generator field coil control terminal, suspect a defective alternator/generator. If the alternator is charging, and the P0622 continues to reset, use the DVOM to test controller power supply fuses and relays. Replace blown fuses as required. Fuses should be tested with the circuit loaded.

- If all fuses and relays appear to be functioning as intended, a visual inspection of controller related wiring and harnesses is in order. You will also want to check chassis and engine ground junctions. Use your vehicle information source to obtain ground locations for related circuits. Use the DVOM to test ground integrity.

- Visually inspect system controllers for signs of water, heat, or collision damage. Any controller that is damaged, especially by water, should be considered defective.

- If controller power and ground circuits are intact, suspect a defective controller or a controller programming error. Controller replacement will require reprogramming. In some cases, you may purchase reprogrammed controllers through aftermarket sources. Other vehicles/controllers will require on-board reprogramming that may only be done through a dealership or other qualified source.
a. The field coil is an integral part of the alternator and cannot usually be replaced separately
b. Test controller ground integrity by connecting the negative test lead of the DVOM to ground
and the positive test lead to battery voltage

[Zack]

That code usually pops up when an alternator with the incorrect regulator is installed

[justbob]

Easyautodiagnostics.com has great write ups on codes, trouble shooting various sensors, and accessories. Very straight forward and broken down in sections specificity related to Ford 4.6 & 5.4


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[Lowndex]

Easyautodiagnostics.com has great write ups on codes, trouble shooting various sensors, and accessories. Very straight forward and broken down in sections specificity related to Ford 4.6 & 5.4


Sent from my iPhone using Tapatalk

Thank you, very helpful.