[AT] Off Topic. Need help with Dodge caravan computer maybe?

[Cecil Bearden]

St eve:
Thanks I will try it.  My thoughts are that the charging syst em 
grounded through a sensor.

Cecil


On 5/18/2017 10:56 PM, Steve W. wrote:
> Cecil Bearden wrote:
>> I know a lot of you guys have more experience with the computer systems
>> than I have.  I have suffered through Youtube videos of nearly every
>> self described ëxpert"in diagnosing a no start condition.  Here's the
>> timeline of what has been replaced and what happened.  Wife's 2003 Grand
>> Caravan w/ 3.8L V6 130000 miles.  Sat Morning, alternator making loud
>> whine heard 40 yds away.  Alternator would burn your fingers after
>> running only 4 minutes.  Dropped Alternator and found noisy water pump
>> also leaking when inspecting other pulleys.  Replaced alternator and
>> water pump after bolt broke off on water pump.  Drilled it out Sat night
>> with cordless screwdriver and hex chuck style bits.  Had partial threads
>> so used a longer bolt and put a nut on back side.   Got it back together
>> on Sunday and had to wait until Mon morning to get some Christmas tree
>> fasteners to hold the belt shield.  Tuesday my wife drove it nearly 150
>> miles in OKC and made at least 15 stops running errands with no
>> problems.  Arrived at front gate and engine died.  Would not start when
>> cranking.  It is possible she stopped and backed up when it died, ( just
>> info for later )  but I cannot confirm.  Found battery ground cable
>> loose after engine would not crank.  Tightened cable and cranked
>> engine.  After several tries the starter would just spin and not engage
>> the flywheel.   Wednesday got reman starter and spent 3 hours removing
>> the old one.  I installed the new starter this morning, and it would
>> crank but not start.  The new starter really grinds, sounds like it is
>> coming apart.  Removed spark plug and cranked with spark plug
>> grounded.   No spark.  Changed ignition coil and still no spark.
>>
>> I don't know where or how to start looking.  Since the battery cable was
>> loose and I took off the ground to install the starter, the codes are
>> not in the computer.  I don't find any method for testing the ECM.
>> There are some forum discussions on the flex plate cracking around  the
>> crankshaft in an octagon pattern and the flex plate shifting.  When this
>> happens, the crank position sensor works on the flex plate, and is then
>> out of time with the cam position sensor.   I cannot find an inspection
>> plate to look at the flex plate.  It would be a 2 day job for me to
>> remove the transmission to look at the plate.  However, I wonder about
>> the original starter just spinning and then the replacement sounding
>> like it is about to fly apart.  If the flex plate is not right, the old
>> starter might have not been able to mesh and the new one is meshing but
>> in a bind.  The old starter had to be pried out of the housing as the
>> nose of the starter was nearly pressed into the bell housing.  The new
>> one was easily pushed into the housing.   So far I have lost over 3 days
>> and nearly $500 working on this when I need to be working on the swather
>> and the water pump on the 1270 Case to pull the swather.  An ECM is
>> another $400, and replacing the flex plate will be at least $600 because
>> I need to send it out.
>> Has anyone had any experience like this?   I know if I take it to the
>> stealership, I will be out $1000 by the time they get done.  I don't
>> have an independent mechanic here I can trust, and if I have to spend a
>> bundle on this car, I am about ready to buy a new one and try to get a
>> 20 year extended warranty!!!  Then maybe I can get some work done.
>>
>> Cecil in OKla
>
> Grab a voltmeter. Turn on the key and test the crank sensor for power
> and ground, It is on the bellhousing right below the crossover pipe for
> the exhaust. 3 wires, Brown/Pink is 8 volt bias voltage, Dark Blue/Dark
> Green is the ground. Brown/Light Blue is the signal wire. If you have a
> scope you would see a square wave on that line.
>
> Easy cheat IF it has a tach, Does the tach move at all while cranking?
>
> Next, disconnect the battery. Hold the two cables together for about 30
> seconds, this will drain the KAM capacitors. Now reconnect the cables.
> Turn on the key and lock/unlock the doors twice.
> See if it starts. You may need to step on the throttle if it acts like
> it wants to start because it will need to relearn the TPS output again.
>
> csr684  at  yahoo  dot com  if you wish to continue.
>