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Re: Does a 97 JGC have a TCU?

On Sat, 27 Nov 2004 14:59:56 GMT, mic canic <dbrider@cac.net> wrote:

>as a jeep dealer tech i'm sorry to say take it to another dealer! 5 hours to tell you that there is no comm.between
>modules can be found out in 5 minutes using a drb3 scantool with it set on module scan. demand some money bac
>i would bet a rookie got yor jeep and not a experenced tech
>depending on the fuel mangement system a jeep can have a tcm but some are part of the pcm

Picked my beloved Jeep yesterday afternoon.
most of the below verbatim, may be one or two typo's from me.

Job 1-
customer states: check engine light is on runs really rough very low on gas ck and rep.
(customer stated "I think I got a load of bad gas, ran it out, stuck some fuel injector cleaner in,worked great till I
filled it up again, and now #1 and #4 dont seem to affect idle when pulled off)
Correction: ckd for engine light on has several different codes stored inj circ open cyl 1p0201 idle cent syst eff p0505
tps cir high ect sensor circ high iat circ high input inj 4 open b 1/1 o2 sensor circ high o2 heaer malfunction bank
1 cyl 1 misfire attempt to scan for all the dtc codes scanner unable to communicate performed diag no results called
star for further assistance ckd ohms and voltages on sci receiver and transmit wires cck and and compared with specs
advised to hot wire sci receiver and transmit wires to bypas ecu to datalink wiring harness this showed ecu is ok and
wir sci tp datalink ok ckd and started tracing for broken wires cdk wiring harness cdk supercard version to assure
update ok advised to eliminate all 5 ref based sensors ckd cam cran tps map bypass cab module to assure its ok it is
compared datalink pin 6&7 voltage reading with or without drb plug in share reading with start aslo noted ecu pins 27
and 29 cdk traced wiring harnesses and found ground at pin 4 of datalin traced ground from below rf headlamp repaired
wire and reass and recheck system able to communicate now and reset codes rechecked with drb able to read now and
communicate with
7$ for sleeves (presumed O-rings on injectors/fuel rail)
3.2$ for cleaner
96.37$ for O2 sensor (what the hay, throw one on there!!!)
780$ labor
Job 2-
Customer states: ck tune up (sure, Im sure it could need it, it only gets 22mpg,well,21.5 unless the Ol'lady drives it
then more like 19)
Correction: cdk tune up cap rotor wires look original and found rotor causing it to arc removed and replaced cap rotor
and wires ck ok now
41.7$ cable pkg
11.7$ cap distr
15.99$ rotor dis
60$ labor

Job 3-
Customer requests a 6cyl spark plug replacement and service platinum plugs require and additional charge
16.2$ worth of sparkplugs
63.25$ labor

Recommendations:
recheck all codes and erased codes still had code for o2 sensor fai removed and replaced o2 sensor cleaned throttle body
with special cleaner and reomved and cleaned injectors and fuel rail installed orings and recheck system again runs
starts and no more light on

Total labor 903$
total parts 189$
tax 79$
JHMFCOAC-1171.97$

The tune up and O2 sensor were approved by me.
I have put off looking under the hood.
(wondering if DOC has any sample "happy pills" before I do!!!!!)
If the ground points have been scraped clean and repainted/greased
and the connectors are "lubed and clean" with no holes poked in wires
I may be very forgiving. If the tank was dropped......................................
This jeep is slated for the junk pile some time in
the year 2020. Unless they no longer sell hard axle jeeps, then I will be forced
to keep on driving "her".

Thank you for your time!

>
>Woodsy wrote:
>
>> Transmission controll unit?
>> I got desperate and took my Jeep to the dealer.
>> It is running bad, pulling the #1 injector wire does not
>> even affect idle, #4 can be felt to make a small differance, but
>> not as much as the other 4. After 5 bill hours, the report is not good.
>> the modules are not communicating with each other(obdII,BCM,ECM,TCM)
>> and the dealer is at the start of the "lets replace" phase. Or it could be a broken
>> wire and "take many hours to trouble shoot".
>>
>> My point of view...
>> Ran great, parked, wife drives 40 miles, gets gas, parks it back where I left it.
>> I get in next morning, runs bad, from first fire on I could tell something is not
>> correct. Tried it for a day or 2,some drygas,some injector bandaid, and it sputtered home, parked
>> and next day, it fired up and ran smooth,(after the injector cleaner)for a while, I ran the tank out, and looked
>> at pulling the fuel rail, the wires and clips seem in good shape, but I chicken'd out.
>> off to the dealer it went, and 2 days later??? I have doubts.
>> i know this is not a lot of information, any help or comments?
>>
>> Frank
>>
>> --
>>
>> Woodsy,
>> Off the Grid, Off the Road, Off my Rocker...

--

Woodsy,
Off the Grid, Off the Road, Off my Rocker...

Re: Does a 97 JGC have a TCU?

Wow!

So there is a main harness ground below the headlight that caused all
that crap?

I for one wouldn't have guessed that in a hundred years....

Sure took the fools a long time to figure out what the computer was
telling them though.....

Thanks for the follow up.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

Woodsy wrote:
>
> On Sat, 27 Nov 2004 14:59:56 GMT, mic canic <dbrider@cac.net> wrote:
>
> >as a jeep dealer tech i'm sorry to say take it to another dealer! 5 hours to tell you that there is no comm.between
> >modules can be found out in 5 minutes using a drb3 scantool with it set on module scan. demand some money bac
> >i would bet a rookie got yor jeep and not a experenced tech
> >depending on the fuel mangement system a jeep can have a tcm but some are part of the pcm
>
> Picked my beloved Jeep yesterday afternoon.
> most of the below verbatim, may be one or two typo's from me.
>
> Job 1-
> customer states: check engine light is on runs really rough very low on gas ck and rep.
> (customer stated "I think I got a load of bad gas, ran it out, stuck some fuel injector cleaner in,worked great till I
> filled it up again, and now #1 and #4 dont seem to affect idle when pulled off)
> Correction: ckd for engine light on has several different codes stored inj circ open cyl 1p0201 idle cent syst eff p0505
> tps cir high ect sensor circ high iat circ high input inj 4 open b 1/1 o2 sensor circ high o2 heaer malfunction bank
> 1 cyl 1 misfire attempt to scan for all the dtc codes scanner unable to communicate performed diag no results called
> star for further assistance ckd ohms and voltages on sci receiver and transmit wires cck and and compared with specs
> advised to hot wire sci receiver and transmit wires to bypas ecu to datalink wiring harness this showed ecu is ok and
> wir sci tp datalink ok ckd and started tracing for broken wires cdk wiring harness cdk supercard version to assure
> update ok advised to eliminate all 5 ref based sensors ckd cam cran tps map bypass cab module to assure its ok it is
> compared datalink pin 6&7 voltage reading with or without drb plug in share reading with start aslo noted ecu pins 27
> and 29 cdk traced wiring harnesses and found ground at pin 4 of datalin traced ground from below rf headlamp repaired
> wire and reass and recheck system able to communicate now and reset codes rechecked with drb able to read now and
> communicate with
> 7$ for sleeves (presumed O-rings on injectors/fuel rail)
> 3.2$ for cleaner
> 96.37$ for O2 sensor (what the hay, throw one on there!!!)
> 780$ labor
> Job 2-
> Customer states: ck tune up (sure, Im sure it could need it, it only gets 22mpg,well,21.5 unless the Ol'lady drives it
> then more like 19)
> Correction: cdk tune up cap rotor wires look original and found rotor causing it to arc removed and replaced cap rotor
> and wires ck ok now
> 41.7$ cable pkg
> 11.7$ cap distr
> 15.99$ rotor dis
> 60$ labor
>
> Job 3-
> Customer requests a 6cyl spark plug replacement and service platinum plugs require and additional charge
> 16.2$ worth of sparkplugs
> 63.25$ labor
>
> Recommendations:
> recheck all codes and erased codes still had code for o2 sensor fai removed and replaced o2 sensor cleaned throttle body
> with special cleaner and reomved and cleaned injectors and fuel rail installed orings and recheck system again runs
> starts and no more light on
>
> Total labor 903$
> total parts 189$
> tax 79$
> JHMFCOAC-1171.97$
>
> The tune up and O2 sensor were approved by me.
> I have put off looking under the hood.
> (wondering if DOC has any sample "happy pills" before I do!!!!!)
> If the ground points have been scraped clean and repainted/greased
> and the connectors are "lubed and clean" with no holes poked in wires
> I may be very forgiving. If the tank was dropped......................................
> This jeep is slated for the junk pile some time in
> the year 2020. Unless they no longer sell hard axle jeeps, then I will be forced
> to keep on driving "her".
>
> Thank you for your time!
>
> >
> >Woodsy wrote:
> >
> >> Transmission controll unit?
> >> I got desperate and took my Jeep to the dealer.
> >> It is running bad, pulling the #1 injector wire does not
> >> even affect idle, #4 can be felt to make a small differance, but
> >> not as much as the other 4. After 5 bill hours, the report is not good.
> >> the modules are not communicating with each other(obdII,BCM,ECM,TCM)
> >> and the dealer is at the start of the "lets replace" phase. Or it could be a broken
> >> wire and "take many hours to trouble shoot".
> >>
> >> My point of view...
> >> Ran great, parked, wife drives 40 miles, gets gas, parks it back where I left it.
> >> I get in next morning, runs bad, from first fire on I could tell something is not
> >> correct. Tried it for a day or 2,some drygas,some injector bandaid, and it sputtered home, parked
> >> and next day, it fired up and ran smooth,(after the injector cleaner)for a while, I ran the tank out, and looked
> >> at pulling the fuel rail, the wires and clips seem in good shape, but I chicken'd out.
> >> off to the dealer it went, and 2 days later??? I have doubts.
> >> i know this is not a lot of information, any help or comments?
> >>
> >> Frank
> >>
> >> --
> >>
> >> Woodsy,
> >> Off the Grid, Off the Road, Off my Rocker...
>
> --
>
> Woodsy,
> Off the Grid, Off the Road, Off my Rocker...

Re: Does a 97 JGC have a TCU?

Mike Romain did pass the time by typing:
> Wow!
>
> So there is a main harness ground below the headlight that caused all
> that crap?
>
> I for one wouldn't have guessed that in a hundred years....
>
> Sure took the fools a long time to figure out what the computer was
> telling them though.....
>
> Thanks for the follow up.

Indeed. Think I will now go out to the ZJ and look at that location.

Woodsy did pass the time by typing:
>>7$ for sleeves (presumed O-rings on injectors/fuel rail)

IIRC, those go over the injectors to add some insulation and prevent
a "rough idle after heat soak" problem.

--
DougW

Re: Does a 97 JGC have a TCU?