2004 grand caravan p0201 p0301

[1987ss]

i have a 04 dodge grand caravan 3.8 with around 137k and we had a few days around 100 deg if it matters and when i drove it it was running rough and would fall flat upon acceleration brought it home n scanned it with generic code reader p0301 and p0201 came up. i also did the key dance and got same codes. one being a missfire cyl1 and other being injector cyl 1. so far i have checked for spark had spark, and changed injector. and no change still getting p0201 on start up. please point me in right direction. thanks
i did a tune up abot 12k ago

[1987ss]

would anyone have a diagram of pcm pinout? or know what pins to check at the pcm? thanks its driving me nuts

[1987ss]

today i pulled the fuel rail harness out and it was melted together with bare wires exposed about 2-3 inches up from plug under the heat shield tape gonna hit salvage yards tomorrow and see what i can find.

[1987ss]

OK i changed harness that was melted and still code P0201 injector cyl 1.. were do i look next? could the pcm have ben damaged when wires in harness melted? does anyone know if i can just get a junk yard computer and swap em? and if i can can i use one from a 3.3 mine has the 3.8 without egr.. PLEASE HELP THANK YOU

[1987ss]

today i swapped the #1 and #3 injectors around and there was no change in code it stayed at cyl1 so i contacted a guy who repairs pcm's and he said theirs 3 drivers for injectors and dose not believe computer to be the issue because only ! injector throwing the code can.. any suggestions will help im very frustrated! Thank you

[1987ss]

today i had pcm checked and the drivers for injectors were good and from drivers to pins was also good.. so i guess i may have to look into the harness better from pcm to fuel rail harness or cut it and run another wire. im unfamiliar with using a multi meter to check wire from pcm plug to the fuel injector any help would be great!! thanks

[1987ss]

it has 12v constant to the injectors injectors all read good on multi meter and the ground is pulsing from pcm.. very confused as to what else will throw a p0201

[bellaCuba]

I would also check for a short to ground along the wire? Be sure to unplug the PCM & injector for the most accurate reading.

[1987ss]

thanks bella. i just rechecked the injector signals all had a pulsed ground execpt for injector 1.. so i put multi meter on the injector plug ground side and touched other end to all the pins on the 4 harness that plug to pcm and the only signal i got was from wire #14 which is the #1 injector.. checked for short to ground with test light didnt find one.

[1987ss]

i found a ecm pcm whatever. mine has no security system and no egr valve and a guy to come to home to reprogram computer with mileage and vin. will it matter if the one i get had a egr and a security system if hes gonna reprogram it?

[bellaCuba]

Let me back up, and understand your previous post correctly. You said you did NOT have an injector pulse for #1... And there is no short to ground?.... BUT it sounds like you have a break in the #1 injector signal wire then. If you must, cut near connector (but not too close to PCM, in case of mistakes ) and attach a new wire directly to the injector that is supposed to be signal. Understand? You would be bypassing the break. You don't even have to install permanently at 1st. Test it by clipping a wire using insulated alligator ends , be sure not to touch any other wires (with key on) or a ground. Use electrical tape if need be, to avoid being knocked down or accidental touching, etc

To answer the last msge, no that PCM would not work. 2 different setups for the engine. The EGR thing would be the issue. It'll throw codes or not run correctly... I believe. I'll see if I can verify that real quick.


Is this AWD or FWD?
When doing the injector pulse tests, use an incandescent test light. Pulses will be clearer than using a meter

[bellaCuba]

Im going to have you do some wiring tests.... unplug the PCM & use the meter on the OHMs setting. Then, test between Pin 6 of the C1 connector (ASD 12v feed) to Pins 7 and then 13-17 for resistance readings. The two PCM connectors are conveniently numbered 1-40 and 41-80 for ease of circuit identification with numbering cast right into the open (terminal) sides of the connectors. They all should be about 15-20ohms each.

This will keep you from hurting this PCM or a new/used one.... depending on the outcome. I hope I didn't throw too much at you all at once....

[1987ss]

i have 4 connectors on the pcm each has 38 pins i dont belive the wire for #1 injector is broke i set multi meter to diode and attached to each end of wire 14 [inj #1] and it comes up 0.000 i will attempt test you just posted it will have to be tomorrow weather permitting.

it is fwd and yes i used a test light to check injector pulse

[bellaCuba]

Ok & good on the latter. Maybe my diagram is off somehow. ooohhh... Grand Caravan... ok, I'll recheck schematics & get back to you there. The thing is, You DON'T want the PCM to get the straight 12v power from the ASD relay. The injectors serve as a resistor to keep that from happening... normally. Which is why with the last set of directions I was essentially testing the circuit "through" the injectors, hence the resistane of 15-20ohms. But the pinout will change since it's a Grand Caravan. I apologize on my oversight.

I'll give you a brief explanation on how the Injectors work with the PCM.
The ASD Relay (Auto Shut Down) provides the 12v ---> it travels to each Injector via Brown wire ---> which then gets grounded in pulses by the PCM

IF somehow the power from the ASD bypasses the Injector, the PCM now get the full 12v on that particular driver in the PCM. Burns it up. So let's say, worst case scenario you need a PCM... you want to make sure all this wiring is good to go, before potentially burning up another one.

Just trying to cover all your bases or help if I can...lol

[1987ss]

thanks bella for the feed back.. i found a ecm at salvage yard 85.00 all #'s matched brought van to dealer swapped ecm's in parking lot they programmed 140.00 it an its running great again!