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No MIL (Check Engine Light) = FAILED inspection?!

12K views 27 replies 13 participants last post by  simmons_tm 
#1 · (Edited)
No MIL (Check Engine Light) = FAILED inspection?! ------> SOLVED!!

I have been going through an ongoing saga of trying to get my Jeep inspected, and I failed again today. I failed before due to bad catalytic converters (codes PO420 and PO432), although my Check Engine Light was not on. I have now replaced everything from the exhaust manifold back with stock components. I went to get it re-inspected today and the cats are good. However, the inspection failed because my Check Engine Light will not come on. A fellow JF member helped me walk through and diagnose that the light is not properly functioning here:

http://www.jeepforum.com/forum/f9/changing-check-engine-bulb-1335275/

Does anybody have any clue as to how to get the light back on? Even when I turn the key to the "on" position the light does not illuminate.

This is beyond frustrating.:confused:
 
#8 ·
It looks like the TJ instrument panel changed during production. I have a 2004 TJ and my panel is different than the one pictured in that thread. I have fewer bulbs than in that panel and the ones that I do not have appear to be in the locations of warning lights. Please see the pictures below for comparison.

Here is the back of my panel:



Here is the panel referenced in that thread:

 
#9 ·
The 2004 TJ has LED's, NOT bulbs. The FSM says they are not serviceable. Being an ex electronic Tech I would say that they probably are if you have the soldering skills. The more difficult problem would be sourcing the replacement parts.
 
#12 ·
Assuming it is an LED, how would someone have gone about diabling that light? The picture above is as far as I disassembled the cluster because I was cautious about opening the white plastic housing. Any harm in going in further? Has anybody opened that before, and if so, would a broken LED be recognizeable?
 
#16 ·
Hi all
Cant be that hard to change out an led, find someone , friends or family that has skills. You are going to replace the unit any way, might save your self @$800 you stated. Besides a unit out of a salvage yard might be way cheaper......................:)P
 
#17 ·
Just for grins try running the Cluster Slef Test to see if the MIL light operates.

(1) Begin the test with the ignition switch in the
Off position.
(2) Depress the odometer/trip odometer switch button.
(3) While still holding the odometer/trip odometer
switch button depressed, turn the ignition switch to
the On position, but do not start the engine.
(4) Release the odometer/trip odometer switch button.
(5) The instrument cluster will automatically
begin the actuator test sequence, as follows:
(a) The cluster will generate a single chime tone
to confirm the functionality of the chime tone generator
and the chime control circuitry.
(b) The cluster will scroll the number "8" across
the odometer/trip odometer VFD to confirm the
functionality of all VFD segments and their control
circuitry.
(c) The cluster will illuminate the decimal point
in the odometer/trip odometer VFD to confirm the
functionality of this VFD segment and its control
circuitry.
(d) The cluster will display the EMIC software
level in the odometer/trip odometer VFD (example:
"SOF 8.9").
(e) The cluster will display the last six digits
(sequence number) of the Vehicle Identification
Number (VIN) in the odometer/trip odometer VFD.
(f) If any faults have been set by the cluster, the
cluster will display the fault information in the
odometer/trip odometer VFD INSTRUMENT
CLUSTER FAILURE MESSAGE . If no faults have
been set, the cluster will scroll "no FAULtS" across
the odometer/trip odometer VFD.
(g) The cluster will turn on, then off again each
of the following indicators, one at a time, in
sequence to confirm the functionality of the indicator
and the cluster control circuitry:​
²​
High Beam

²​
Brake

²​
Seatbelt

²​
MIL

²​
Check Gauges

²​
Low Fuel

²​
4WD

²​
SKIS

²​
Cruise

²​
Upshift
(h) The cluster will sweep the needles for each of
the following gauges, one at a time, to several calibration
points in sequence to confirm the functionality
of the gauge and the cluster control circuitry:

²​
Speedometer

²​
Fuel

²​
Temperature

²​
Tachometer

²​
Voltage

² Oil Pressure
 
#26 ·
Victory is mine. :thumbsup:

On a related matter, I hope my Jeep's previous owner enjoys a special kind of hell reserved for idiots of the highest order.

As stated above, I decided to go ahead and remove my instrument panel, again, and completely take it apart. I removed the back cover and quickly found that nothing here seemed to be able to address my problem:



I then flipped over the panel and held a flashlight near the black surface to find the MIL. Oddly enough, the outline of the light was much darker than the others - this gave me pause. I then started trying to shine the light under the black surface of the panel to see if the light would shine through the back side of where the MIL is supposed to be - nothing. The light was clearly coming out of the "Check Gauges" indicator, but not the MIL right next to it. Upon closer inspection, just below the surface of the instrument panel's face, something was amiss:





Ever so slightly glued (only on the edge) I found this piece of black plastic wedged behind the face of the instrument panel. It appears to be a simple rectangle cut out of a black, plastic or vinyl folder. Some @#$!%$@^&%&! had stuck it back there because he was tired of looking at his check engine light. :nono: And now?

Here it is with the key in the "On" position:



An here it is with the engine running:



Thanks for all of your posts in trying to help me figure this out! I guess we at least figured out a real cheap way to turn off your MIL.
 
#27 ·
I know this thread is a year old, but I just ran into pretty much the same problem. My garage also would not pass my jeep for the MIL. Except when I took my cluster apart, i found the LED had been ripped from the board. If anyone else runs into this, a $2 Radio Shack LED and someone with soldering skills is all you need. No reason to replace the entire cluster.

To get to the LED you have to take those 24 screws out, they hold the servo motors that control the needles on your gauges. The main circuit board will pop right out after that. Looking at where the LED should be, the board is marked with the letter "K" on the top and left side and the letter "A" in the bottom right corner. "K" is negative and "A" is positive. ( fun fact "K" is used to mark relays on circuit boards) I bought a $2 surface mount LED that was rated for 2-2.4 volts. (took a shot in the dark) It has an intensity of 29 mcd and is almost as bright as the factory lights. My cousin who is much better at soldering than I am soldered it on and I will be back to the garage as soon as I can.

As the OP said...I hope my jeep's previous owner enjoys a special place in hell reserved for child molesters and people who talk at the theater.
 
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