[Tim Schmidt]

2000 dodge caravan 2.4 L 210 000 miles
Had the van parked for 3 weeks now it wont start.
no power to the fuel pump, coil, starter.
I can jumper the starter solinoid and turn the engine over but theres no spark and i can not hear the fuel pump start.
My neibor stopped in with a code reader and says the pcm ecu has no power, the code reader would not read or connect with the computer.
I have checked the grounds to the engine and chassie.
I have checked all the fuses under the hood and the front fuse box near the battery.
I have also swapped out the relays for the ing and the auto shutdown.
What shall i check next?

 

[ImperialCrown]

Check for powers and grounds at the PCM. The Rd/Wt wire should have 12 volts battery power. The Wt/Bk wire should have 12 volts with the ign on. Both Bk/Tn's need to be a good ground. With these in place, the scan tool should be able to communicate with the PCM.
The Dk.Gn/Or wire from the ASD relay is powered by fuse #3 in the underhood (PDC) fuse/relay box. It also powers the PCM and ign coil. It has power for a couple of seconds after theign is turned on and turns back off if the PCM doesn't detect engine rotation through the crank position sensor.
If the 5 volt (Vt/Wt) or 8 volt (Or) sensor wire outputs from the PCM are shorted to ground, the PCM will go into protection and not communicate either.

 

[royce70]

Another place to look is a ground wire beneath the battery tray, if chrysler did not change anything. That was the problem with our 05. Even though you say you checked your grounds, you should be pulling them apart, cleaning and reassemble with anti seize. Just because they look good does not mean, they are fine. It cost us over 500.00 for a garage to find this problem. The part that I don't understand was the bill had a 40.00 electrical kit put on. WTF. Any way check it out, to make sure that there is not another ground that may have been missed. The garage had to go through the front tire well to get to it.

 

[Tim Schmidt]

IC i will check for power at these location tuesday.
royce i have checked those grounds i removed the batt tray and removed the nut cleaned and re tightened the connection no change there.
I will not get a chance to work on it again till tuesday evening.

 

[Tim Schmidt]

ok tonight i checked some of the items on your list.
i did the checks with both the large plug connections removed from the pcm.
the Rd/Wt wire had 5 volt reading with the ing off.
the Wt/Bk wire has 2.45 volts with the ing on.
both of these wires were on the gray faced color block.
also on the gray faced block was a Bk/Tn with good ground.
There was a Bk/Tn on the black faced block that was also good ground.
the Dk. Gn/Or wire was on the black faced block and showed no voltage in the ing on or off position and i had the test meter where i could see it when turning the key and there was no voltage at any time.
not sure where this puts me but with all the twisting moving around and pokin and proddin the vans condition remains the same DOA.

Check for powers and grounds at the PCM. The Rd/Wt wire should have 12 volts battery power. The Wt/Bk wire should have 12 volts with the ign on. Both Bk/Tn's need to be a good ground. With these in place, the scan tool should be able to communicate with the PCM.
The Dk.Gn/Or wire from the ASD relay is powered by fuse #3 in the underhood (PDC) fuse/relay box. It also powers the PCM and ign coil. It has power for a couple of seconds after theign is turned on and turns back off if the PCM doesn't detect engine rotation through the crank position sensor.
If the 5 volt (Vt/Wt) or 8 volt (Or) sensor wire outputs from the PCM are shorted to ground, the PCM will go into protection and not communicate either.

 

[ImperialCrown]

That sounds like the problem. You will need to back-trace towards the underhood fuse/relay box (PDC) to find out where you are losing the 12 volts on the Rd/Wt and Wt/Bk wires.
Being near the battery could cause corrosion issues on the connectors and wiring underneath the PDC. Examine this area.

 

[Tim Schmidt]

Ok we got it solved thanks for the direction imperialcrown.
Stopped by the local garage and the owner printed out some of the wiring diagrams for me.
when i pulled the green connection from the under hood pdc there were 2 wires corroded from the plug pins after trying to see the colors the 2 wires broke free from their bad connections 1 was the red with white stripe the other was right next to it same side.
I went out back i have a 97 caravan parts car and the pdc looks much different but when rotating it over the same green 10 pin plug was right there ripe for the picking.

After cutting splicing soldering and assembly the old girl started right up.
WHOOOHOOO.

 

[ImperialCrown]

Good work!