Engine Light

I live in California and have a 2000 Jeep Cherokee Sport. Occasionally
(perhaps once a year) the engine light will come on. I'll get antsy and plan
to take it in for service. But the light only stays on for a couple of hours
then goes off. I mention this to the service guys and because the light
isn't on, they have no clue.

What sort of problem causes the engine light to come on?

"Alan" > wrote:

> I live in California and have a 2000 Jeep Cherokee Sport.
> Occasionally (perhaps once a year) the engine light will come on.
> I'll get antsy and plan to take it in for service. But the light
> only stays on for a couple of hours then goes off. I mention this
> to the service guys and because the light isn't on, they have no
> clue.

Shouldn't the Check Engine Light set a code in the computer? Shouldn't
the service guys know how to read the code and see what set it? I
think you're correct when you say, "..they have no clue."



--
XS11E, Killing all posts from Google Groups
The Usenet Improvement Project: http://blinkynet.net/comp/uip5.html

"Alan" > wrote in message
...
>I live in California and have a 2000 Jeep Cherokee Sport. Occasionally
>(perhaps once a year) the engine light will come on. I'll get antsy and
>plan to take it in for service. But the light only stays on for a couple
>of hours then goes off. I mention this to the service guys and because
>the light isn't on, they have no clue.
>
> What sort of problem causes the engine light to come on?
>
Go to an Autozone and get them to read the codes that the system puts into
the computer when the light goes on (they do that for free, no problem).
Then report them here and the folks here can tell you what they mean and
what to do.
Tomes

Hi Alan,
Pull the codes: http://www.wjjeeps.com/faultcodes.htm More than likely
it's just a loose gas cap. http://www.billhughes.com/faultCode.mpg
God Bless America, Bill O|||||||O


"Alan" > wrote in message
...
> I live in California and have a 2000 Jeep Cherokee Sport. Occasionally
> (perhaps once a year) the engine light will come on. I'll get antsy and
plan
> to take it in for service. But the light only stays on for a couple of
hours
> then goes off. I mention this to the service guys and because the light
> isn't on, they have no clue.
>
> What sort of problem causes the engine light to come on?
>
>



--
Posted via a free Usenet account from http://www.teranews.com

Since this happens for just a few hours once a year, a loose gas cap would
fit the symptoms. But since all who replied have said to "read the codes" --
and I'll do that -- I assume that whatever caused it to come on is stored in
the computer -- kind of like a diary -- even though the light itself has
long since gone off.


"L.W. (Bill) Hughes III" > wrote in message
.. .
> Hi Alan,
> Pull the codes: http://www.wjjeeps.com/faultcodes.htm More than likely
> it's just a loose gas cap. http://www.billhughes.com/faultCode.mpg
> God Bless America, Bill O|||||||O
>
>
> "Alan" > wrote in message
> ...
>> I live in California and have a 2000 Jeep Cherokee Sport. Occasionally
>> (perhaps once a year) the engine light will come on. I'll get antsy and
> plan
>> to take it in for service. But the light only stays on for a couple of
> hours
>> then goes off. I mention this to the service guys and because the light
>> isn't on, they have no clue.
>>
>> What sort of problem causes the engine light to come on?

Alan proclaimed:

> I live in California and have a 2000 Jeep Cherokee Sport. Occasionally
> (perhaps once a year) the engine light will come on. I'll get antsy and plan
> to take it in for service. But the light only stays on for a couple of hours
> then goes off. I mention this to the service guys and because the light
> isn't on, they have no clue.
>
> What sort of problem causes the engine light to come on?

Loose gas cap?
....and change service guys.

Alan wrote:
> I live in California and have a 2000 Jeep Cherokee Sport. Occasionally
> (perhaps once a year) the engine light will come on. I'll get antsy and plan
> to take it in for service. But the light only stays on for a couple of hours
> then goes off. I mention this to the service guys and because the light
> isn't on, they have no clue.

hi everyone. i also have a '00 xj and the engine light came on with a
code of : P1694, 0141, & 0455. anything serious?
thanks in advance,
doo

http://www.wjjeeps.com/faultcodes.htm
P1694
Fault In Companion Module
No CCD/J1850 messages received from the powertrain control module-Asian
transmission.

P0141 (M)
O2 Sensor Heater Circuit (Bank 1 Sensor 2)
Oxygen sensor heater element malfunction. O2 sensor voltage greater than 3
volts for 60 to 240 seconds.

P0455 (M)
Evaporative Emission Control System Leak Detected (large leak)
A large leak has been detected in the evaporative system. See TSB
25-001-02. Also, possible faulty or loose gas cap. Note: The respective
Powertrain Diagnostic Procedures Manual will direct the technician to
determine if the vehicle evaporative system has an external system leak.
Examples of some external system leaks a a loose gas cap, a disconnected
evaporative system hose, or a loose hose connection. Remember that the
evaporative system may also have an internal system leak. This internal leak
may be caused by an intermittent or permanently stuck open Duty Cycle Purge
(DCP) valve. This leak source is considered to be internal because any
escaping emissions enter into the engine system and not directly into the
atmosphere, unlike an external leak. An internal leak may cause one of the
above DTC?s. Possible causes of a stuck open (intermittent or permanent) DCP
valve a 1. Corrosion due to system moisture or possible water intrusion
into the system.
God Bless America, Bill O|||||||O
http://www.billhughes.com/


"Dooly" > wrote in message
oups.com...
>
> Alan wrote:
> > I live in California and have a 2000 Jeep Cherokee Sport. Occasionally
> > (perhaps once a year) the engine light will come on. I'll get antsy and
plan
> > to take it in for service. But the light only stays on for a couple of
hours
> > then goes off. I mention this to the service guys and because the light
> > isn't on, they have no clue.
>
> hi everyone. i also have a '00 xj and the engine light came on with a
> code of : P1694, 0141, & 0455. anything serious?
> thanks in advance,
> doo
>



--
Posted via a free Usenet account from http://www.teranews.com

Dooly wrote:
> Alan wrote:
>> I live in California and have a 2000 Jeep Cherokee Sport. Occasionally
>> (perhaps once a year) the engine light will come on. I'll get antsy and plan
>> to take it in for service. But the light only stays on for a couple of hours
>> then goes off. I mention this to the service guys and because the light
>> isn't on, they have no clue.
>
> hi everyone. i also have a '00 xj and the engine light came on with a
> code of : P1694, 0141, & 0455. anything serious?
> thanks in advance,
> doo
>
P1694 is Tachometer Circuit High Voltage. I'm not familiar with the "O"
codes.

--
FRH

Go to Autozone and check out the Scan Tool from the Loaner Tool rack. You
can easily plug the scan tool into the data port and operate it to see what
the computer has stored. They will take your driver license and let you take
the tool outside. You can take the tool home if you like, but they will
charge your Visa then give full credit back to the Visa when you return the
scan tool. If the car can be driven, I'd just use the scan tool in front of
the store, but if you have a car that won't run, then you can take the tool
home to troubleshoot.

I'll take a guess that the codes that are stored are in a range of P0440 to
P0456, which generally point to the gas cap. Specifically, these codes are
the Evaporative Emissions Control System, which is the system that controls
gas fumes. There are many causes of "fume leaks", but as a general rule, the
gas cap is frequently leading the list of usual suspects.




"Alan" > wrote in message
...
>I live in California and have a 2000 Jeep Cherokee Sport. Occasionally
>(perhaps once a year) the engine light will come on. I'll get antsy and
>plan to take it in for service. But the light only stays on for a couple of
>hours then goes off. I mention this to the service guys and because the
>light isn't on, they have no clue.
>
> What sort of problem causes the engine light to come on?
>