Hi,

I have come across the Key trick to get the OBD codes if any present, I now have a short shopping list of codes. While not yet concerned I need to know do these codes clear themselves over time, or do they remain listed in memory until reset using a code scanner or similar? Furthemore do some of the errors not raise the Check Engine Light, as this light only came on when I unplugged the MAP sensor.

I have the following in my basket:
P0110
P0235
P0514
P0579
P1130
P1685

I tested the Check Engine Light by unplugging the MAP, so P0235 and maybe P0110 is related to that test. P0514 may go hand in hand with my occasional battery fault light coming on (suspect the battery has almost exceeded it lifespan).

P1130 - Heated Oxygen Sensor Circuit Low (is that on the exhaust)?
P0579 - Never knew of any issue on cruise control
P1685 - Skim key invalid (equally never tried an invalid key)

Thanks,

_________________
2007 2.8CRD Cherokee Limited Auto
Ex. 2002 2.5 CRD Limited

[[I have the following in my basket:
P0110 - Intake Air Temperature voltage too hi or lo - MAP sensor
P0235 - Boost sensor voltage too hi or lo - MAP sensor
P0514 - Batt Temp rationality - output does not change as expected, can cause other errors
P0579 - Cruise multifunction switch circuit A
P1130 - Unspecified in CRD system - could be anything for those OTHER engines with O2 sensors
P1685 - Unspecified in CRD system
I tested the Check Engine Light by unplugging the MAP, so P0235 and maybe P0110 is related to that test. P0514 may go hand in hand with my occasional battery fault light coming on (suspect the battery has almost exceeded it lifespan).
P1130 - Heated Oxygen Sensor Circuit Low (is that on the exhaust)?
P0579 - Never knew of any issue on cruise control
P1685 - Skim key invalid (equally never tried an invalid key) ]]

Other than the disconnected MAP sensor DTC's, errors from various unrelated points could be corrosion\oxidation in the connectors, frayed wiring, etc - disconnect each connector, scrutinize the pins and wiring - if ok, reconnect and go to the next one - also the battery temp fault can cause several other codes, such as the O2 sensor code, of which sensor the CRD has none of, being a Diesel

_________________
'05 CRD Limited
Pricol EGT, Boost
GDE Hot '11; EDGE Trail switched
SEGR; Provent; Magnaflow;
Suncoast T\C, Transgo Tow'n'Go switch;
Cummins LP module, Fleetguard filter, Filterminder
2.5" Daystar f, OME r; Ranchos; K80767's, Al's lifted uppers
Rubicons, 2.55 Goodyears
Four in a row really makes it go

Thanks,

What you say about the battery does make sense, I think milking the battery for a little extra life has come to an end. It has died on me everytime I have left the Jeep for 5 or more days. I get back to a stone dead vehicle. I did jump start it the last time, have heard many rumours that modern day vehicles with onboard computers don't like this.

_________________
2007 2.8CRD Cherokee Limited Auto
Ex. 2002 2.5 CRD Limited

Great care is necessary when jump-starting with a dead battery, particularly with a charger that has the high-output BOOST\START switch - if one cell is open or highly resistive due to calcification, full charger voltage is applied to the electronic modules which should never have more than the max system charging voltage applied, which is around 13.8v

Jump-starting shouldn't cause a problem if using another battery for the boost

Also, for a DTC test, disconnect the MAF over on the airbox duct, rather than the MAP - it will give the traditional 0102, but the vehicle is otherwise driveable as normal (but with increased power!) with no defueling or limp-mode operation

_________________
'05 CRD Limited
Pricol EGT, Boost
GDE Hot '11; EDGE Trail switched
SEGR; Provent; Magnaflow;
Suncoast T\C, Transgo Tow'n'Go switch;
Cummins LP module, Fleetguard filter, Filterminder
2.5" Daystar f, OME r; Ranchos; K80767's, Al's lifted uppers
Rubicons, 2.55 Goodyears
Four in a row really makes it go