Won't Start

[baggman]

Have replaced Crank Position sensor and Magnetic Pick Up Sensor (located under distributor cap). Have checked all relays/fuses under hood.
Fuel pump will not prime(installed six months ago).
Parked Jeep and came back out to start ten minutes later - would not start. Overhead display only shows hash marks. Fuel gauge and battery gauge on dash will not move when I turn switch on. Check engine light does not appear to disappear with other lights. Low fuel icon shows after all other lights go out.

 

[SteelHeadz]

I'm a little confused with the chain of events. It was running fine then it just quit?, then you replaced the CKP and the CMP then the fuel pump?. The Overhead display shows "Hash marks"? .

 

[baggman]

I'm a little confused with the chain of events. It was running fine then it just quit?, then you replaced the CKP and the CMP then the fuel pump?. The Overhead display shows "Hash marks"? .

Sorry for the confusion. I was trying to be brief... Let's start over.
The jeep was running. I had just drove the kids home from school. I went back out to the jeep after a short time(maybe ten or fifthteen minutes) only to find that it would not start. I noticed that the check engine light wasn't showing up with the other dash lights. You know, like when you turn on the ignition, they all light up and then they all go off. All the lights except the check engine come on and go out. The low fuel icon comes back on. I also noticed that the fuel pump was not making the whirring sound it makes when you turn on the ignition. I was told before that these symptons could be caused by the crankshaft position sensor or thr the camshaft position sensor. I replaced the crank sensor first...nothing, so I replaced the cam sensor...still nothing. Had put in a fuel pump about six months ago. Have checked all fuses under the dash and the ones under the hood. Not sure how to check the relays correctly(there are several prongs). Someone suggested the computer box could be gone, but I don't how to test for that either.The overhead disply usually show shows compass reading, miles per gallon, distance til empty,etc. Now, there are only two hash marks on the display. Not sure what else to do. Don't want to keep buying parts I don't need. Thinking it might be an oversight since the thing was running. NEED HELP!

 

[baggman]

I'm a little confused with the chain of events. It was running fine then it just quit?, then you replaced the CKP and the CMP then the fuel pump?. The Overhead display shows "Hash marks"? .

Sorry for the confusion. I was trying to be brief... Let's start over.
The jeep was running. I had just drove the kids home from school. I went back out to the jeep after a short time(maybe ten or fifthteen minutes) only to find that it would not start. I noticed that the check engine light wasn't showing up with the other dash lights. You know, like when you turn on the ignition, they all light up and then they all go off. All the lights except the check engine come on and go out. The low fuel icon comes back on. I also noticed that the fuel pump was not making the whirring sound it makes when you turn on the ignition. I was told before that these symptons could be caused by the crankshaft position sensor or thr the camshaft position sensor. I replaced the crank sensor first...nothing, so I replaced the cam sensor...still nothing. Had put in a fuel pump about six months ago. Have checked all fuses under the dash and the ones under the hood. Not sure how to check the relays correctly(there are several prongs). Someone suggested the computer box could be gone, but I don't how to test for that either. Not sure what else to do. Don't want to keep buying parts I don't need. Thinking it might be an oversight since the thing was running. NEED HELP!

 

[FloridaCherokee1988]

Even though you replaced the fuel pump 6 months ago it could still be the pump man, check your wires going into your fuel pump with a test light, if there's power goin to your pump but it's not working then it's the pump, if there's no power going through those wires at all and you've already replaced your crank and cam sensor then check for a fuel pump relay, could be a cheap relay went out and shut off the power to your pump.

 

[SteelHeadz]

X2. also diagnose the inop overhead Issue. The blank screen indicates that it's not communicating with the BCM and or the PCM. If there's issues with these modules, the vehicle will have a no start condition. Try removing the overhead console and disconnect the electrical connector. Try to start the vehicle. if a no start still exist, the problem is NOT on the Overhead module. Check the ASD relay as well.

 

[baggman]

X2. also diagnose the inop overhead Issue. The blank screen indicates that it's not communicating with the BCM and or the PCM. If there's issues with these modules, the vehicle will have a no start condition. Try removing the overhead console and disconnect the electrical connector. Try to start the vehicle. if a no start still exist, the problem is NOT on the Overhead module. Check the ASD relay as well.

Am grateful the advice, but am not familiar with BCM and ASD.
Could you please elaborate?
Thankx

 

[baggman]

Even though you replaced the fuel pump 6 months ago it could still be the pump man, check your wires going into your fuel pump with a test light, if there's power goin to your pump but it's not working then it's the pump, if there's no power going through those wires at all and you've already replaced your crank and cam sensor then check for a fuel pump relay, could be a cheap relay went out and shut off the power to your pump.

Thanks....After all it is a man made product. Will try it today.
Any way you help me on testing a relay? There are several prongs.....

 

[Herbert Rogers]

How frustrating! My '99 2WD Sport is also NOT starting. No warning, whatsoever! Engine turns-over nicely. All electronics seem to work nicely,
except my LCD reads: NO BUS
What? "No Bus" ? What does that mean? Oh yes, when I turn the key...the guages don't move.
Any suggestions?

 

[jb21366]

Have replaced Crank Position sensor and Magnetic Pick Up Sensor (located under distributor cap). Have checked all relays/fuses under hood.
Fuel pump will not prime(installed six months ago).
Parked Jeep and came back out to start ten minutes later - would not start. Overhead display only shows hash marks. Fuel gauge and battery gauge on dash will not move when I turn switch on. Check engine light does not appear to disappear with other lights. Low fuel icon shows after all other lights go out.

What year is it and what engine? Replace the auto shut down relay in the underhood fuse box. The only catch is that it is the only relay like it so you would have to buy one. Luckily they are cheap. If no Check Engine Light you would have to diagnos that. The ASD relay fires up the computer when yoou turn the key on.

 

[Herbert Rogers]

I'm assuming you are addressing me...not baggmann....
(If you are) Many thanks. Oh yes, my '99 has an Inline 6cyl .
I checked my Fuse Box. The ASD and Fuel Pump fuses are Identical.
Is that suppose to be?

 

[Herbert Rogers]

Sorry jb21366...I just re-read your reply.

 

[jb21366]

I'm assuming you are addressing me...not baggmann....
(If you are) Many thanks. Oh yes, my '99 has an Inline 6cyl .
I checked my Fuse Box. The ASD and Fuel Pump fuses are Identical.
Is that suppose to be?

No the ASD is all by itself. It looks the same but internally different. It powers up the fuel pump relay. You cannot switch them, learned from experiance. When key on power should run thru all terminals. The green and orange wire off of that relay powers CMP CKP TPS ignition coil, injectors and eventually grounds in the PCM. Check for power at the ignition coil. If none I would definetly go back to the ASD relay. Also my YJ liked to shut off whenever it felt like. I found a bad connection near the motor mount at the green and orange. (Not a good thing to happen to an automotive instructor). I went nuts replacing CMP, CKP, coil, ASD twice, until I accidentally found it. So I am sharing my knowledge with you
Good Luck let me know what you found.

 

[SteelHeadz]

How frustrating! My '99 2WD Sport is also NOT starting. No warning, whatsoever! Engine turns-over nicely. All electronics seem to work nicely,
except my LCD reads: NO BUS
What? "No Bus" ? What does that mean? Oh yes, when I turn the key...the guages don't move.
Any suggestions?

Along with the symptoms you mentioned, no spark?. Disconnect the CKP sensor and see if the gauges moves and the "no bus" on the cluster goes away after you turn the key on. If it does, replace the CKP sensor. Don't forget to check all the fuses and connections related to the instrument cluster.

 

[54cj3b]

try disconnecting batt to reset comp

 

[jb21366]

How frustrating! My '99 2WD Sport is also NOT starting. No warning, whatsoever! Engine turns-over nicely. All electronics seem to work nicely,
except my LCD reads: NO BUS
What? "No Bus" ? What does that mean? Oh yes, when I turn the key...the guages don't move.
Any suggestions?

What engine and does the Check Engine/Service Engine Soon light come on when you turn the key to the run/on position?
No Bus means your walkin, no it means that a communication breakdown is occurring between diagnostic and the computer. Check fiuses, all of them. Some are protecting battery positive and some might protect ground. Point is they should all show continuity with an ohm meter. Give me more info and when I get to work I will look some things up.

 

[jb21366]

I am assuming that this is a tj sport. Try this. Take a volt meter and locate the diagnostic link connector (DLC) under the left side of the dash. Ground the black lead on the meter to a good ground (any bare metal will work). At the DLC probe terminal/pin 3 (violet/brown), with the red lead and see if you have around 2.5 volts. Do this to terminal/pin 11 (white/black) wire also. Should be around 2.5 volts. If anything else than around 2.5 volts you have a module on the blink. Module s on the buss lines include;Key Immobilzer Module, Air Bag Control Module,PCM,TCM, Overhead (if equipped), Compass (if equipped), and Instrument Cluster IC. Locate them and unplug one at a time and retest each time you disconnect one.
Also try disconnecting both cables from the battery, holding both disconnected cables in your hands touch them together for 30 seconds or so. Then reconnect to battery and try to start. What that does is reset all the modules by draining the memories. This causes the modules to have to relearn and maybe it might get you to fire.
Good Luck

 

[baggman]

A bad crank position sensor will sometimes cause a no start. With the switch on, notice if the check engine light comes on and goes out with all the others. If it doesn't show, then you probably won't hear the fuel pump prime(the whirring sound you get when you turn on the ignition switch). The gauges won't move either. Try replacing the crank sensor. the first thing you will notice is the gauges move and the pump primes. The check engine light will show and go away with the others. Should start....Hope this helps.