Engine not starting.

you need to check the bulb in the dash see if its good check for power at the plug for the obd

Your chipped key is not making a good connection to your factory installed anti-theft device. Lightly grease both sides of car key with electric bulb grease and work it into key ignition. Over time the key wears down, contacts in ignition switch become worn and corroded. Grease makes better contact...chipped key is able to send signal to factory anti-theft device which unlocks all systems required to start you engine. Make sure the key you are using is a chipped key for your car; not a un-chipped cut key from the key cutting machine. It will work on locks, but only a chipped key for your car will deactivate your anti-thief and you get power to your engine and systems to get it started.

fuse number 24 is a 30 amp fuse goes to pcm relay and fuse number 30 the 30 amp fuse to ignition to pcm power diode.if check light is working your pcm has power but you could have short in the dlc connector terminal where you scanner adapter goes.your scanner suppose power up from the dlc terminal for obd 2 system the obd 1 you connect to cigarette light or use battery hook up cables that come with scanner make sure you are using correct adapter.

3 digits. follow this link for more info. Good Luck.
http://autorepair.about.com/library/ts/obd-i/bl-dtcs-98.htm

How to Replace a Throttle Position Sensor
(DIY & Save up to $135.75 ) - Time: 2.1 hours

Parts:
1. Throttle Position Sensor - $ 55.44

Tools:
1. Scan Tool
2. Screwdriver
3. Multimeter

Procedure:
1. Locate the OBD data link connector (DLC). Refer to your owner’s manual for the specific location.

• Tip: The OBD-I data link connector is usually located in the engine compartment near the battery or the fuse box. The OBD-II connector (post 1995 cars) is usually located beneath the instument panel next to the steering column.

2. Turn your key to the“ON” position. Do not start the engine.

3. Plug your scan tool into the OBD data link connector. Turn on the scan tool and select the appropriate steps to read the diagnostic trouble code (DTC).

Scanner plugged into OBD-II data link connector.

• Tip: The OBD-II diagnostic trouble code (DTC) is a 5 character alphanumeric code. The first digit is a letter that indicates the component group, the second digit is OBD mandated or manufacturer specfic, the third digit is a subgroup, and the fourth and fifth digits define the component and basic problem.
  

• 4. Locate the throttle position sensor.

• 
  
• Throttle position sensor
  

• 5. Disconnect the electrical connector from the throttle position sensor.

• 
  
• Electrical connector removed
  

6. Test the resistance of the throttle position sensor (TPS) with a digital multi-meter. If the resistance is out of specifications, the TPS must be replaced.

• 7. Remove the throttle position sensor.



Removing sensor mounting screws

8. Install the new throttle position sensor. Tighten the mounting screws and attach the electrical connector.

• 9. Erase the diagnostic trouble code (DTC) with the scan tool using the“delete” or“erase” command. Road test your vehicle to see if the check engine light returns.

Check engine light


• Tip: If the check engine light returns, repeat the diagnostic process for additional DTCs or take your vehicle to a certified repair shop.

Direct OE replacement

Hope helped with this. Good luck (remember rated this help).

To query and OBD-I-era computer for these codes, put the key in the ignition and turn the key to run (not start), then off, then run, then off, then run (that's 3 runs and 2 offs). Leave the key in the run position.

The check engine light will turn on for a few seconds, then turn off, then (sometimes after 20-30 seconds) start flashing. The flashes are counting out 2-digit trouble codes. Fast flashes count up each digit, with a longer pause between digits. On TJ's with a digital odometer, the code numbers are printed on the odometer in addition to flashing the check engine light. 55 indicates the end of all codes. Once you've got your code list, consult the table below to see what they mean.

OBD-II information is more complex, so the codes for 1998 and newer Jeeps can't be displayed by flashing the check engine light. However, those vehicles which have digital odometers will display the codes on the odometer. I've verified this personally on a 1999 WJ. For those vehicles without digital odometers, or for anybody who wants an English description rather than just a numeric code, an OBD-II code scanner ($100-300) can be plugged in under the dash. OBD-II codes can be looked up online here.


These codes were taken from the '95 XJ/YJ factory service manual.

I hope help you woth this. Good luck (rated this).

Can't take an OBD-0/pre-OBD car to auto zone as only OBD-2 cars have a hook up for the scanner.

Sounds like the igniton switch. close to the same happened to my z-34 except it just wouldn't start one time the ignition switch has something that reads a chip in the key, (security thing) the wire inside the switch broke so it wouldn't read the key chip which in turn wouldn't send any electricity to the pcm.I had to have it replaced (believe it or not its a big job) and buy the key which was like, if I remember right, $50-$100 for the key itself plus lots of labor hours.

OBD 2 (96-2008) does not have that capability, older systems did up to the 1995 model year. You can buy a tester that does just codes on ebay for less than $40.00, live data stream testers are about double that.