injector coil fuse blows when crank

Hello,

Your vehicle keeps blowing the fuse because there is a short to ground in the circuit[s] that that fuse is protecting. This happens because of Ohm's Law, the laws that govern electricity in a vehicle. Ohm's law states that if one of the three properties of electricity stays constant, and one always is in an automotive circuit [Voltage-there is constant battery voltage] and one of the remaining two goes down[Resistance-resistance goes to zero as the electricity has a direct path back to the negative battery terminal] than the last property must go up proportionally [Amperage-Amperage will go to the Amperage rating of the battery]. The Amperage/Current or the flow of electricity will overtake the fuses amperage rating and "pop" the fuse blows, protecting the circuit, just like it was designed to do. In the diagrams down below I have included a wiring diagram of your vehicle's Coil On Plug circuits and a guide on how to find short to grounds in an automotive electrical circuit. You will need to use a Digital Multi-meter [DMM] to do go through this guide. Here is a link below explaining how to use one, if needed:

https://www.2carpros.com/articles/how-to-use-a-voltmeter

Please go through these guides and get back to with what you are able to find out.

Thanks,
Alex
2CarPros

There's no ground wires in the injector or ignition coil circuits, so if you grounded something, that would be what is shorted. Both circuits are grounded by the Engine Computer. It switches the grounds on for the injectors to pulse them for a few milliseconds, and it switches the grounds off for the ignition coils, individually, when they need to create the spark.

The first diagram has fuse # 24 circled. That feeds circuit F42 dark green / light green for the six injectors. The two circuits are continued on the second diagram at call outs "I" and "J". This is the circuit that has to be shorted for that fuse to blow.

If you aren't sure if the short is something you caused, another way to find this is to replace the blowing fuse with a light bulb. That will limit current flow in the circuit to safe value, and give you a visual indication of when the short is present or removed. Normally I stick a 3057 brake light bulb in place of the fuse, but for anything related to the automatic shutdown, (ASD) relay, which this is, it's better to bypass the relay instead because that relay only gets turned on for one second when you turn on the ignition switch. Obviously that is not enough time to do any testing. The relay gets turned on again during engine rotation, (cranking or running), but since the engine doesn't run, any testing would have to be done while a helper is cranking the engine. Again, not practical.

The way to do this is to install a good fuse into socket #24. Don't turn the ignition switch on or that fuse will blow again. Now, remove the ASD relay, then stick in two universal crimp-type spade terminals into the socket's terminals 30 and 87. That's if you have the common 1" cube relays. If you have the skinnier relay like the one shown on the right of the drawing, use the two terminals the arrows are pointing to.

Use a pair of small jumper wires to connect those two terminals to the light bulb. A 3057 brake light bulb has easily accessible terminals and will limit current to one amp. It can get pretty hot when it's at full brightness, so be careful where you lay the bulb.

By connecting the bulb across the relay socket, the circuit will be energized all the time. No need to turn the ignition switch on, and there won't be nearly enough current to blow the new fuse. If the short is present, the bulb will be full brightness. Now you can move wire harnesses around, unplug things, and disconnect connectors to see what removes the short from the circuit. When you find something that removes the short, the bulb will get dim or go out completely.

I just noticed they changed the relay terminal numbering, but the physical locations are the same. Use terminals 82 and 84. Two small red arrows are pointing to them in the fourth diagram.

i have f42 wire grounded is that supose to b grounded to the valve cover or is it a hot wire

i guess that is the wrong wire. my problem is when i took off valve cover there were 1 or 2 wires on diodes an on 1 on regular grounds i some how the diode broke up this is this the f42 i put the diode back with missing parts the other wire was cut off some how really short, but it was green so i extended it and grounded it. the other is green with black strip coming from the wires coming up from starter. it was cut off just naked wire showing. please disregard first message.

typo for diodes capacitor/condenser seems like that is the green and light green wire on one broken capacitor possibly.

Hello again,

No. The f42 wire is a hot wire coming from the ASD Relay pin 30, or possibly pin 87 and is the wire supplying power to the component to be power[Coil[s]]. It should not be grounded. This is your short to ground.

Thanks,
Alex
2CarPros

yes, i cut it an the fuse stopped blowing but that wire was connected to a capacitor and screwed to the top of the valve cover. am i crazy?

Still didn't crank but it's getting plenty of gas now. i can smell it. where does this wire go? there is one on each side but 25 didn't blow just 24.
also is there anyway you could show me the grounds that go to the valve covers? there were two capacitors and maybe 2 ground on the valve cover that i can't find any except for this broken capacitor.

There's no capacitors, diodes, or ground connections in those circuits. Can you post some photos of what you're working with?

parts number 4606866aa this one is 4 an 04, but it is the same thing/picture the capacitor was on both valve covers. if not where does this wire go green light green wire? as soon as i cut that wire the fuse stopped blowing and i could smell a little gas.

this is at the end of that wire an it screws down on valve cover screw first valve cover screw is tightened down then the capacitor is placed on top of that same screw its about 1 inch then screwed down with another screw smaller size. Then the green with light green strip has a prong the plus right into the capacitor.which again is broken some peaces missing from old capacitor there is one onm each valve cover.

Hello,

Okay, this looks like an Radio/Ignition Capacitor for collecting the Electro-Magnetic Frequency[EMF] from the ignition coils and storing it then releasing it to ground of the vehicle battery. When your coils release the electricity that is built up in the winding's of the coil to produce the electricity to make the spark plugs spark, it creates a collapsing magnet pulse that gives of EMF and will be picked up by any unshielded wiring. So it is the job of these capacitors to collect and disseminate the EMF to the vehicle's ground. A good example of what happens when these capacitors aren't working is if you have ever accelerated in a vehicle and the more you accelerated the louder a whining hum would come over the vehicle's speakers, that hum is the EMF from the ignition coils being collected by the speaker wires instead of the capacitor.

Thanks,
Alex
2CarPros

Hello again,

Here are the wiring diagrams with the positive wires to the Coil On Plugs[COP][s] and fuel injectors and the capacitors highlighted for you in the diagrams down below. I hope this helps.

Thanks,
Alex
2CarPros

Can i bug you one more time? could you show me the grounds there is a green with black stripe and i have it grounded to the valve cover. just want to make sure it is right. thank you

Hello again,

Where is the wire originating from? If you know.

Thanks,
Alex
2CarPros

i don't. it is rapped up with a bunch of other wires. i am trying to find the ground that go onto the valve covers for this car. i am thinking it is a ground. i don't see it on the hot wire diagram you showed me. is there a ground diagram?

it seems like from your diagram that the black with dark green strip is coming from the power train control module to the oxygen sensor. i grounded it thinking it was a ground wire then I cut it just to see a difference. still wont start.

Hello again,

Okay, in the diagrams down below I have sent the entire set of ground distribution wiring diagrams from the vehicle manufacturer. I hope that this helps.

Thanks,
Alex
2CarPros

Thanks Alex. i am so grateful for your help.

Alex i have tor the car down took valves off an changed cam sensor after looking at so many videos seems like i am not getting any power to fuse 25,24 from auto shut down the auto shut down is working. i used test light also swapped fuses the relay is good but when i turn key an test b24,25 no power at all.

Hello,

Check Fuse 14. It supplies power to the power side of the relay. Please get back to us with what you are able to find out.

Thanks,
Alex
2CarPros

Okay, i didn't check fuse check 14 yet not home,but when i disconnected the fuel rail gas came out only when key was turned i can here pump fuel didn't come out at crank or just at key being forward also took valve off chain is still tight an seems like all tensioners are working. also changed cam sensor, but the 24 25 just did not light up during test with key forward, but with key forward auto shut down did light up two pins left an top pin lit on all relays. they all lit up at same pins plus swapped relays around.

14 is good all lghts up an then swapped them around.

Hello again,

Okay so let's check the dark green/orange wire from pin 6 of the PCM connector to splice 108 of the engine harness for an open. In the diagrams down below I have included a guide on how to find an open in an automotive electrical circuit for you. Please go through this guide and get back to us with what you are able to find out.

Thanks,
Alex
2CarPros

where is the guide?

question, i cut both radio noise capacitors off an threw in garbage could this be the problem? do i need the capacitors grounded? right now there are no capacitors on the green light green wires.

Hello again,

I'm sorry. I forgot to put the the guide in the previous reply. Here is the guide for how to find an open in an automotive electrical circuit that I promised earlier. The capacitors collect the Electro Magnetic Frequency [EMF] that results from the collapsing magnetic field of the coils used to fire the spark plugs and then routs it to a ground. This frequency can interfere with crankshaft/camshaft sensor signals, and is famous for causing a hum in the speakers of your car stereo. But first let's check the wire for an open that we talked about earlier, please. Please go through it and get back to us with what you find out.

Thanks,
Alex
2CarPros

Alex, i am not real good with the multi meter, but the connection seems fine per instructions. i didn't find any opens on the green/orange wire but when i change the relay inside the car same type of relay the fuses 24/25 both lit up the probe. when i turned key forward in cranking mode test light light up. i used the fan wire an got a new radio frequency capacitor, but car still no crank.

*typo i used fan relay.

Hello again,

Okay, so I think we are going to be down to a bad Powertrain Control Module[PCM] or "computer". Fuse 24 provides power to all of the coils and fuel injectors, so if your test light is lighting up and you still are a no start then that leaves the other half of the circuit, and the PCM controls both the coils and the fuel injectors by providing and breaking ground, which obviously isn't happening in your vehicle's case. It's not the end of the world, I had to replace the PCM in my personal vehicle just a couple of months ago for the same thing, no start, no spark and no fuel injectors, so it can be done. Please get back to us with what you decide and we can go from there.

Thanks,
Alex
2CarPros

Hello again,

Scratch my last reply. I was thinking about this some more and something occurred to me, where did you cut the dark green/light green wire that is going to each of the Ignition capacitors [noise suppressors] at? In the diagrams down below I have included the same set of wiring diagrams as I have previously sent, but this time I went and got the Original Equipment Manufacturer [OEM], or Chrysler's wiring diagrams instead of the non-OEM wiring diagrams. You can clearly see that the noise suppressor is a parallel circuit in the ignition coil circuit, and could be the short to ground that is causing the problem, but I believe it's the old COP that is being used has the short to ground in it, then either way if the wire is cut before anywhere in the circuit before the first dot[directly underneath the from S138's on diagram 5] then it would create an open in each banks COP circuit and cause a no start, but the short to ground would also have no electricity going to it and fuse 24 wouldn't blow. Please go through these guides and get back to us with where the dark green/light green wire was cut at and we can go from there.

Thanks,
Alex
2CarPros

i cut the green light green wire right at the capacitor just to take capacitor of so capacitor is grounded and mines was broken into pieces. so i just cut it off. i took maybe 1 inch of wire off along with capacitor.

also if i change PCM would it have to b reset at a dealer or just as long as i get same year an all it plug an play.2nd i did do the water pump but i am pretty sure i did a good job putting timing back i lined up all sprockets an marks an set the primary tenssioner then rotated motor by hand two times an marks lined right back up done i dint move came as it was not a rest timing it was a water pump but could it b the time off i don't get any codes for cam or crank when i turn motor.

Hello again,

Okay, so if you cut the wire there then we might be looking at a bad PCM. As far as getting the timing chain/belt lined up with the timing marks, if you are able to turn your engine over a couple of times through the four stroke process with no resistance when turning it by hand, other than the resistance of turning an engine over by hand, then you are in the clear for being off on the timing, it's right. That wouldn't cause a no start from no spark either. Having said this, I have included in the diagrams down below the instructions for the removal and installation of your vehicle's ECM/PCM, along with the requirements when replacing said ECM/PCM. It will have to be reprogrammed to the Sentry Key Immobilizer Module[SKIM] at the dealership. I have also included the price for parts and labor for your vehicle's ECM/PCM should you decide to go that way. It looks like the cost for your ECM/PCM, removal and installation, and reprogramming will cost less than I paid for my PCM, used. To get the labor rate take the installation and reprogramming time add them together and then multiply that sum by the hourly shop rate in your area to come up with the labor cost. Also, please pay special attention to the highlighted areas of the guides, and whenever replacing anything electrical on your vehicle, disconnect the negative battery cable BEFORE you start. This will negate any power spikes from damaging sensitive electrical components. Please go through these guides and get back to us with how everything is progressing.

Thanks,
Alex
2CarPros

question, so i unplugged the cam sensor car crank right up the cam wheel was put on back wards buy mistake and i was tapping on it with a hammer and screw driver to force it to seat looks like after realizing it was backward. i can see some small dents on the very outside rim. could this be an issue an since car did crank? could it still be a PCM?

Hello again,

Yes it would. In the diagrams down below I have included exactly what happens with your vehicle in "Start Up" mode. Please go through this guide and get back to us when done. We can go from there with CMP wheel replacement instructions.

Thanks,
Alex
2CarPros

Wow too vague. i am asking do you still think i new PCM? and why even though car cranked up without cam plugged in.also can i take computer to dealer and have programmed or do i need to take car and all?Thanks

also, this motor was changed it is not the original. i don't remember programming the PCM for the used motor and i drove it for 2 years. I do not know.

Hello again,

Yes, I still think that your vehicle's ECM/PCM has bad drivers in it. If you read what I sent last time, it says that when the ignition switch is turned to "start" and the ECM/PCM receives both CKP and CMP signals it will energize the ASD Relay, which your vehicle does, but the fuel injectors or ignition coils are not getting power, which only leaves the drivers from the ECM/PCM. You can have your vehicle's keys programmed to the new ECM/PCM either at the dealership or by a locksmith. There are no other options here.

Thanks,
Alex
2CarPros

Okay, thank you so much.