Lincoln Repair Questions? Ask a Mechanic for Answers ASAP
Hello and thank you fro your question,If 30 amp fuse 12 for the air suspension compressor in the power distribution box repeatedly blows due to a dead short, the problem is most likely a defective air suspension compressor. To verify the short is not in the harness, unplug the air suspension compressor connector, remove the compressor relay from the power distribution box and install a jumper wire between terminals 30 and 87 in the relay box. If the fuse does not blow, the harness is OK. In most cases, the problem is due to excessive moisture in the compressor causing it to corrode. This is usually caused by leaking rear air bags allowing moisture to enter the system. To repair, if the compressor can be disassembled, cleaned it out and lubed it. In cases where it can not be disassembled, the compressor will need to be replaced. In either case, a new dryer assembly will need to be installed and any system leaks must be repaired to prevent a repeat failure.
Does the engine start and run?
Yes I know that, dose the engine start and run?
Actually it shuts off power to the coils. I would start with taking a close look at the engine harness to each coil looking for a short to ground and if that checks okay then try unplugging one coil at a time and see if the fuse holds. See the circuit wiring diagram in the link below for reference. Copy and paste the link to your browser to open and view it.https://dl.dropboxusercontent.com/u/104923897/Fuse%20%2312%20Jun%2018.pdf
Your engine has coil on spark plug which means you have 8 coils, one on each spark plug. You can unplug one at a time and it will still run, before you do that take a close look at the engine harness to each one of them.
If its a failing coil unplugging one at a time will tell you which one is shorted simply by turning on the key, You do not have to start it.
Yes but before you do that take a close look at the engine harness to each coil for any signs of a short to ground. If you do not see any issue with it , then do one coil at a time.
The post remains open as long as you need me. Be sure to check the harness First.
Okay then start the engine with is disconnected and see if it will start and run . If so and the fuse hold then either the harness to it is shorted or the coil is.
I would try swapping the #1 coil with the #2 coil and see if the fuse blows again and if it does then the coil is bad and needs to be replaced.
Okay then that sure point to a bad coil.
Did you not say it started with #1 unplugged and ran?Did you ever look at the harness to all of the coils?
Your looking at the harnesses to each coil for any signs of where it may have rubbed through and touching ground. If it stay running with the #1 coil unplugged the the problem is with the coil or the harness to it.
Then I would be looking very close at the harness to that coil.
If the coil is shorted then yes it should . Im not convinced just yet it is. Chasing a short to ground can be a real SOB as you are finding out. Lets see what happens .
Just for the hell of it while its running go back out and pull on the engine harness in and around the other coils and see if its stays running.
Okay then you are still dealing with a short in the circuit.
I suspect its in the circuit you working on but I can not say for sure.
You do not want to by pass the fuse, its blowing for a reason, you have to have a short to ground and if you by pass it you could smoke the harness. You need to locate the short.
Back at the coil and the engine harness. Something is being over looked here.
The air bag flashing means the system is seeing a fault and should be setting a fault code for this and its not likely related to the blow fuse. Im off today but will return on Monday if you do not get this resolved before then