The glow plug control module is right behind the battery. You may want to check it and makes sure it has power and is functioning properly?

Relay is functioning. Using a test light shows all 4 wires sending voltage to the glow plugs. I'm thinking about putting my original ceramic plugs back but it's cold out there! One thing I noticed was on initial ignition the relay was sending power for about 15 seconds but the glow plug light would only light up for 3 seconds.

Your results are fairly standard. Try 3 consecutive (immediate) cycles of the glow plugs for 5 seconds each cycle. It should rumble and smoke like crazy, but it should start. Or, plug it in for 20 minutes or more and it will start much easier.

Edit: do 2 or 3 of the 3x5 second cycles if necessary. Some of these jeeps are more stubborn than others.

Battery is good. I can turn the engine over for 15 minutes Just noticed the glow plugs I ordered from IDparts were the 7v Etechno. Didn't know they sold 3 different kinds... Apparently these are worthless. They shouldn't even be selling these if they are that bad. I ordered the 5v Bosch so hopefully that will solve that mystery.

Be sure and post the results of installing the 5v plugs. It may help some others...

I hope you didn't change the glow plug module / reprogram for 5 volt system

Never mind followed the tips and tricks link. Found out I had no continuity on #4 so I reached around and pulled the connector and low and behold the plastic housing had broke and only half of it still there. Now I need to find a replacement. In the mean time I plugged it in and covered it in electrical tape. Not bad considering the jeep started right up this morning with only 3 of the 4 working.

CONCLUSION: Etechno plugs suck.

Hopefully this may be of help?

Mopar Connection Repair Kit:
FUEL INJECTOR NO. 4 (DIESEL) - BLACK 2 WAY
Full Repair Kit: 05143779AB
http://connectors.dcctools.com/home.htm

I too was puzzled by the short time the glow plug indicator was on. In the manual, I found the the time the glow plugs are ACTUALLY ON, as related to coolant temperature. This was shown below (more succinctly), but here it is again, directly from the manual for the CRD, page 8i-25:
(sorry for all the dots... this site doesn't recognize spaces so I had to fill them in with something).

engine coolant temp......wait-to-start lamp......Pre-heat cycle (time..........Post-heat cycle
.....with "Key on"...............time "ON"................plugs are on B4 start).....time on (after start)

...-30 C / -22 F.....................10 sec ......................35 sec ........................200 sec
...-10 C / 14 F......................10 sec ......................23 sec ........................180 sec
...+10 C / 50 F......................1 sec ......................21 sec ........................160 sec
...+30 C / 86 F......................1 sec ......................20 sec ........................130 sec
...+ 40 C / 104 F....................1 sec ......................19 sec ........................140 sec
...+ 70 C / 158 F....................1 sec ......................16 sec ........................ 20 sec

So big surprise to me... the glow plugs are ALWAYS operating for a while, just for a different length of time depending on coolant temp, even when the engine is warm. So when starting in the winter.... WAIT 22 seconds after seeing the indicator go out in 1 sec, or lasts even 10 sec if its below -10C/14F. THEN YOU HAVE ACTUALLY USED THEM PROPERLY.

DUH on Jeep.... like they couldn't leave the light on for the actual pre-heating time? Really?