No bus help

[jonesnoahr]

Alright so I'll aim to give you guys as many details as possible. Ill start by saying I've searched quite extensively on this and found a bunch of threads and articles but nothing seems to work. My 4.0 6spd 2006 TJ wont start when I turn the key. No cranking, nothing. All lights work, radio works, etc. Ive checked all the fuses, cleaned all the connections, replaced the crank sensor because i heard thats a common fault. I tested PCM and get 12v power and 5v supply. Grounds test good. When I hold trip button and turn key I get Sof 5.1 and Bus b0, b1, and b8 followed by open panel. I took a remote start system out immediately before this happened but the jeep started right up and drove fine afterwards. Then I turned it off and it wont start back up. I do not hear fuel pump engage with key. Dials on gauge cluster do not move except during testing. Fuel light comes on (half tank full), key symbols comes on and stays solid. Check engine light will come on a few seconds later and stay on.

You guys have any idea what else to check or try? or is it time to give up and take it to a dealer with a DRB111 tool?

 

[Chris]

Alright so I'll aim to give you guys as many details as possible. Ill start by saying I've searched quite extensively on this and found a bunch of threads and articles but nothing seems to work. My 4.0 6spd 2006 TJ wont start when I turn the key. No cranking, nothing. All lights work, radio works, etc. Ive checked all the fuses, cleaned all the connections, replaced the crank sensor because i heard thats a common fault. I tested PCM and get 12v power and 5v supply. Grounds test good. When I hold trip button and turn key I get Sof 5.1 and Bus b0, b1, and b8 followed by open panel. I took a remote start system out immediately before this happened but the jeep started right up and drove fine afterwards. Then I turned it off and it wont start back up. I do not hear fuel pump engage with key. Dials on gauge cluster do not move except during testing. Fuel light comes on (half tank full), key symbols comes on and stays solid. Check engine light will come on a few seconds later and stay on.

You guys have any idea what else to check or try? or is it time to give up and take it to a dealer with a DRB111 tool?

It sounds like you've done quite a bit of troubleshooting already. The fact that you're not getting any cranking at all makes me think it could be a problem with the starter or starter relay. Have you tried jumping the starter directly to see if it will turn over? Also, have you tested the starter relay to make sure it's functioning properly? Additionally, the fact that you're not hearing the fuel pump engage could mean there's an issue with the fuel pump relay or the pump itself. It might be worth checking those out as well. If you've exhausted all possible options, it might be time to take it to a dealer to have them run a diagnostic with the proper tool.

 

[jonesnoahr]

It sounds like you've done quite a bit of troubleshooting already. The fact that you're not getting any cranking at all makes me think it could be a problem with the starter or starter relay. Have you tried jumping the starter directly to see if it will turn over? Also, have you tested the starter relay to make sure it's functioning properly? Additionally, the fact that you're not hearing the fuel pump engage could mean there's an issue with the fuel pump relay or the pump itself. It might be worth checking those out as well. If you've exhausted all possible options, it might be time to take it to a dealer to have them run a diagnostic with the proper tool.

I just threw my harbor freight remote starter on the bottom bolt of the starter solenoid and the positive of the battery, it whirred like normal but didnt crank the engine. I'm sure it wasn't getting enough amperage to actually engage but it did move. Ive switched the relays around too, no dice.

 

[jonesnoahr]

I just threw my harbor freight remote starter on the bottom bolt of the starter solenoid and the positive of the battery, it whirred like normal but didnt crank the engine. I'm sure it wasn't getting enough amperage to actually engage but it did move. Ive switched the relays around too, no dice.

There is a small blue wire under the steering wheel that may have shorted but I cant figure out what it's connected to or what damage it would have done if no fuses blew

 

[jonesnoahr]

There is a small blue wire under the steering wheel that may have shorted but I cant figure out what it's connected to or what damage it would have done if no fuses blew

Reading through the FSM it looks like its the ground sensor wire for the clock spring. it may have gotten 12v for a few seconds. Anybody think that would cause this?

 

[Minderbinder3]

You sure your key chip hasn’t gone bad? Sometimes the key works the ignition but doesn’t send the code to start. Not sure if your ‘06 had this feature. My 2000 does not

 

[Daryl]

key symbol comes on and stays solid.

If the key symbol is lit solid, that indicates an issue with the SKIS. Try a different key.

 

[jonesnoahr]

You sure your key chip hasn’t gone bad? Sometimes the key works the ignition but doesn’t send the code to start. Not sure if your ‘06 had this feature. My 2000 does not

The key is chipped, and there is a SKIM. But even if the chip went bad, It wouldn't stop the guages from working or engine cranking. I tried starting with a non chip key before and it just cranked forever but wouldn't start

 

[jonesnoahr]

If the key symbol is lit solid, that indicates an issue with the SKIS. Try a different key.
View attachment 425558

Yea, I saw that too. But would it stop the guages from working?

 

[Daryl]

Yea, I saw that too. But would it stop the guages from working?

You need to diagnose one issue at a time. I would inspect all the wiring from the removal of the remote start system. From what you stated, everything worked fine until you removed that. What do the wiring harnesses look like? Does it look factory or has it been hacked up?

 

[jonesnoahr]

You need to diagnose one issue at a time. I would inspect all the wiring from the removal of the remote start system. From what you stated, everything worked fine until you removed that. What do the wiring harnesses look like? Does it look factory or has it been hacked up?

I've gone through all the wiring. I don't see anything cut or out of place. The remote start system was installed using a bunch of line taps, no wiring was actually cut. And the vehicle did start and drive after removal. Do you know if there's any specific connections or wires I need to check more thoroughly?

 

[jonesnoahr]

Should the asd relay be powered with ignition on?

 

[Daryl]

Should the asd relay be powered with ignition on?

For three seconds, then if the engine hasn’t started it de energizes. Also the stupid wire taps are like a guillotine and can cut the wire in two when removed, even if the insulation is still intact.

 

[sab]

I just threw my harbor freight remote starter on the bottom bolt of the starter solenoid and the positive of the battery, it whirred like normal but didnt crank the engine. I'm sure it wasn't getting enough amperage to actually engage but it did move. Ive switched the relays around too, no dice.

Your statement that "it whirred like normal but didnt crank the engine" confuses me. When the solenoid is energized, two things occur. First the solenoid's actuator and mechanism kick the starter gear out to engage the flywheel gear. Second, the starter contact is engaged, supplying energy to the starter motor to make it turn the starter gear. When you say it "whirred like normal" do you mean that the starter gear moved and then the noise stopped? If so, then either your starter is bad, or the positive and negative for the motor are not making good contact somewhere. If the noise continued, then you may have teeth missing on the flywheel and the starter gear is spinning freely (if so, you need to manually turn the crankshaft to get to a portion of the flywheel where there are teeth).

This doesn't explain some of the other problems, but if you directly engaged the starter solenoid, the starter should turn the crankshaft (although the engine obviously won't start). You're bypassing all the other systems when you do that.

 

[jonesnoahr]

I gave all the wires a tug to see if theyd pull out of the taps and none did. Also I would think there would be issues as soon as the wire is put in the tap then. the style used had the spade connected so you can add and remove wire without doing anything to the tap. Also I jumped the starter at the solenoid and it cranked properly. I also bypassed the ASD and that did not help.

 

[Daryl]

I gave all the wires a tug to see if theyd pull out of the taps and none did. Also I would think there would be issues as soon as the wire is put in the tap then. the style used had the spade connected so you can add and remove wire without doing anything to the tap. Also I jumped the starter at the solenoid and it cranked properly. I also bypassed the ASD and that did not help.

Show me a picture of these wire taps.

 

[jonesnoahr]

Your statement that "it whirred like normal but didnt crank the engine" confuses me. When the solenoid is energized, two things occur. First the solenoid's actuator and mechanism kick the starter gear out to engage the flywheel gear. Second, the starter contact is engaged, supplying energy to the starter motor to make it turn the starter gear. When you say it "whirred like normal" do you mean that the starter gear moved and then the noise stopped? If so, then either your starter is bad, or the positive and negative for the motor are not making good contact somewhere. If the noise continued, then you may have teeth missing on the flywheel and the starter gear is spinning freely (if so, you need to manually turn the crankshaft to get to a portion of the flywheel where there are teeth).

This doesn't explain some of the other problems, but if you directly engaged the starter solenoid, the starter should turn the crankshaft (although the engine obviously won't start). You're bypassing all the other systems when you do that.

no I think i just didnt have good contact on it. When I jumped the relay manually it engaged as it should and cranked the engine. Still no start though

 

[jonesnoahr]

Show me a picture of these wire taps.

 

[jonesnoahr]

Per some others suggestions, I tried another troubleshooting technique. I jumped the relays for asd (thus disabling it), the fuel pump (i could hear it turn on), turned the key to the on position, and then jumped the starter relay to crank the engine. I let it crank for 10ish seconds but no start.

 

[jonesnoahr]

How exactly does the SKIM stop the car from starting? I dont think its that because Ive had a spare made in the past that didnt have the chip. It just cranked forever and wouldnt start. The Bus messages of b0, b1 and b8 and the gauges not moving make me think the issue is somewhere in the wiring or pcm. Aside from testing the 12v pin, the 5v wire and the grounds, I dont know any other way to test it. Testing all the wires individually from harness to pcm would be next to impossible with the equipment I have