Cranks but no start (codes P0688 and P0522)

1RAD

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The firmware within the PCM is not very robust and can often report multiple failures when in actuality only a single issue exists, which is why you always troubleshoot the most serious problem first. This fact may explain the lack of additional codes assuming there is a faulty sensor. The PCM doesn’t appear to be seeing the ASD sense signal during startup.

Parts fail, the timing of the failure can be random, semiconductors especially fail when initially energized (like a lightbulb). Simply because it ran fine then sat for a week really doesn’t mean much.

So yes, you could have been stranded.

I really don’t think installing LED lights has any bearing on the issue you are experiencing.
 
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garagecouple

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The firmware within the PCM is not very robust and can often report multiple failures when in actuality only a single issue exists, which is why you always troubleshoot the most serious problem first. This fact may explain the lack of additional codes assuming there is a faulty sensor. The PCM doesn’t appear to be seeing the ASD sense signal during startup.

Parts fail, the timing of the failure can be random, semiconductors especially fail when initially energized (like a lightbulb). Simply because it ran fine then sat for a week really doesn’t mean much.

So yes, you could have been stranded.

I really don’t think installing LED lights has any bearing on the issue you are experiencing.
Thank you!

Here are some updates,

Removed asd relay and jumped power between 87 and 30 pin. It fired right up and runs strong. It seems like for some reason the pcm isn't allowing the relay to activate. Because it worked after I jumped the pins, I'm thinking I should change the CPS and see if that fixes it. Any other suggestions? Thanks so much!
 
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garagecouple

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Sounds like you are on the right track....
Removed the crsnk and cam shift position sensors cleaned and reinstalled. Still same no start as before. Going to order replacements now. Are there any other sensors or parts I should order ?
 

1RAD

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Those are the only two. If at all possible be sure to get Mopar sensors instead of aftermarket, they tend to work better or at least last longer.
 
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garagecouple

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Thanks for this, it is extremely helpful. If it is the cam or crank sensor, wouldn't it throw one of those respective codes? Wondering if the led tail lights caused this. Still baffled that it happened after sitting for a week with the previous drive smooth as ever. What if I was on a trip or overlanding or far away from home? Would have left me totally stranded.
Ok great. Ordered a Mopar crankshaft position sensor. They don't make a camshaft position sensor so ill go with smp.

Thanks for all the help. Will keep you posted!
 
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1RAD

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Ok great. Ordered a Mopar crankshaft position sensor. They don't make a camshaft position sensor so ill go with smp.

Thanks for all the help. Will keep you posted!

Thank you!

Here are some updates,

Removed asd relay and jumped power between 87 and 30 pin. It fired right up and runs strong. It seems like for some reason the pcm isn't allowing the relay to activate. Because it worked after I jumped the pins, I'm thinking I should change the CPS and see if that fixes it. Any other suggestions? Thanks so much!
After reading this again, the fact that the engine started and ran fine indicates the sensors are functioning. It would be a good idea to verify the wiring/relay socket for the ASD. (Loose/broken wire, corrosion). You did swap the ASD with a known good relay? I apologize for any confusion.
 
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garagecouple

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After reading this again, the fact that the engine started and ran fine indicates the sensors are functioning. It would be a good idea to verify the wiring/relay socket for the ASD. (Loose/broken wire, corrosion). You did swap the ASD with a known good relay? I apologize for any confusion.
I swapped the ASD with two other known working relays and still the same issue. After jumping pin 30 and 87 on the ASD, it fired right up! I did get 4 new codes, all for the oxygen sensors. I'm assuming those popped up because I jumped the asd.

I checked the ASD wires as well as the tsb work, everything appears to be intact.

I'm not sure how those wires would go bad after being parked for 1 week. Sequence of events, jeep was fully operational no hiccups. It was parked and then would not start (cranks forever). All I did in between was install led tail lights.

So far I've checked the asd relay and checked all fuses both in the glove box and in the PDC. Everything looks fine.

I ordered crank shift sensor, cam shaft sensor, 4wd switch sensor, and oil sender sensor. Was planning on swapping those 4 and seeing what happens. What else should I be doing and looking for? I just don't understand why the asd circuit would take a dump after sitting for a week.
 

1RAD

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That would suggest that the PCM is not supplying the ground to the ASD during cranking. You stated earlier that you verified both the ASD relay and fuel pump relay were closing with the key in the run position?
 
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garagecouple

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That would suggest that the PCM is not supplying the ground to the ASD during cranking. You stated earlier that you verified both the ASD relay and fuel pump relay were closing with the key in the run position?
Thank you for all of your help! Im sorry, I don't quite know what a relay closing means.

When I crank the key, the relay clicks, then the fuel pump wines, and then the relay clicks a second time. I have tested the horn relay in this slot and also the same thing occurs. The PCM isn't providing a ground to the ASD - I wonder if this is because one of the sensors is not functioning properly. I wonder what else I can check to see why the PCM isn't grounding the ASD relay.
 

1RAD

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Thank you for all of your help! Im sorry, I don't quite know what a relay closing means.

When I crank the key, the relay clicks, then the fuel pump wines, and then the relay clicks a second time. I have tested the horn relay in this slot and also the same thing occurs. The PCM isn't providing a ground to the ASD - I wonder if this is because one of the sensors is not functioning properly. I wonder what else I can check to see why the PCM isn't grounding the ASD relay.
There are two relays and they activate almost simultaneously when everything is functioning correctly, you know the fuel pump relay is closing because you can hear the pump running, but did you specifically verify that the ASD relay is closing (clicking on, then off)? You are confident you are not mistaking the sound from the the fuel pump relay for that of the ASD?

If the engine runs with a jumper across the ASD, the sensors are functioning. The issue is with the relay or relay circuit.
 
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garagecouple

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There are two relays and they activate almost simultaneously when everything is functioning correctly, you know the fuel pump relay is closing because you can hear the pump running, but did you specifically verify that the ASD relay is closing (clicking on, then off)? You are confident you are not mistaking the sound from the the fuel pump relay for that of the ASD?

If the engine runs with a jumper across the ASD, the sensors are functioning. The issue is with the relay or relay circuit.
Thanks for that info! I had my wife put her finger on the asd relay and she says it clicks twice when i turn the ignition.

I don't think it is the relay itself, i tested 3 different relays and the problem persists.

Regarding the circuit, i mean it was all cut apart and re soldered together as part of the jeep tsb 25 001 07. In summary: PDC cavity A13 corresponding to ASD pin 85 was cut (which leads to fuel pump relay). Next the wire connecting ASD pin 30 to fuse #9 (ASD power) was cut. I attached a diagram of the changes that were made to the circuit via the tsb.

tsb jeep.JPG
 

AjRagno

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TSB 25-001-07
2005 TJ FSM (ASD Relay Testing is Page 410)
ASD Relay Explained

Yes, you should hear 2 relays click when the ignition is cycled to ON. One is the fuel pump relay and the other is the ASD relay.

You really should have a multi-meter for trouble shooting and do not replace any more parts without testing the wiring.

The ASD Relay receives power via the #9 20A fuse and the PK/RD wire in the PDC. Without power, the ASD relay will shut down the ignition and fuel injectors.

I understand the 02 sensor TSB was performed about a week before the issue started. You said that you inspected the wiring but the splices should have heat shrink covering them so you'll need to test the wiring for continuity.
 
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garagecouple

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TSB 25-001-07
2005 TJ FSM (ASD Relay Testing is Page 410)
ASD Relay Explained

Yes, you should hear 2 relays click when the ignition is cycled to ON. One is the fuel pump relay and the other is the ASD relay.

You really should have a multi-meter for trouble shooting and do not replace any more parts without testing the wiring.

The ASD Relay receives power via the #9 20A fuse and the PK/RD wire in the PDC. Without power, the ASD relay will shut down the ignition and fuel injectors.

I understand the 02 sensor TSB was performed about a week before the issue started. You said that you inspected the wiring but the splices should have heat shrink covering them so you'll need to test the wiring for continuity.
Thank you for the information!

Read the reference material (even before you posted it), and appreciate your insight! So, how would you go about testing the wiring with a multi-meter? Should I undo the tsb and put it back to the original configuration? I don't understand how one moment it drives fine, then after being parked it doesn't fire up.

In any case, its a 15 year old vehicle and I am happy to replace old sensors with mostly mopar replacements.

I did the tsb myself. I used shrink tubing but I also crimped the wires exactly per the tsb.

Thank you for the help,
 
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garagecouple

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Correct, at this point it’s very likely the circuit wiring.
Appreciate that. I think I will go ahead and install the 4 new sensors and see what happens. If still nothing, I will undo the TSB and see if that fixes my issue. I would imagine that if something was wrong with the ASD ground wire, it would blow the ASD fuse, but testing the fuse with my multimeter shows almost 0 and that there is continuity.
 
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garagecouple

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Triple post but just writing my thoughts here as I wait for the products.
So we are all on the same page:

A11 - pin 85 - pcm ground
A13 - pin 86 - 12v switched power
A14 - pin 87 - 12v power out to fuel pump
A15 - pin 30 - constant 12v.

After the tsb, both pin 30 and pin 86 were connected, thus both are always +12v which is what I see on the multimeter.

A11 which is pin 85 and the ground from the PCM wasn't touched by the tsb. The fact that the jeep activates the relay momentarily tells me the ground is fine and that the pcm is physically able to ground the relay. I think this issue is upstream the asd relay. I think one of the sensors is off and thus telling the pcm to deactivate the ASD.

As you can see I'm clearly losing my mind here. Really don't want to undo the tsb as this allowed me to pass smog and it drove great after performing it. I wish there was more information on the web.
 

1RAD

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Those sensors are nothing more than switches, they either work or they don’t.

A14 does not go to the fuel pump, that is the output to the PCM. The fuel pump relay is totally independent and controlled by the PCM.

If A13 & A15 were connected together the relay would always be energized.

A11 - Control ground from PCM
A13 - Switched ignition 12v
A15 - Fused B+
A14 - Switched B+ to PCM, Coil, Injectors
 
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garagecouple

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Those sensors are nothing more than switches, they either work or they don’t.

A14 does not go to the fuel pump, that is the output to the PCM. The fuel pump relay is totally independent and controlled by the PCM.

If A13 & A15 were connected together the relay would always be energized.

A11 - Control ground from PCM
A13 - Switched ignition 12v
A15 - Fused B+
A14 - Switched B+ to PCM, Coil, Injectors
Thanks for the correction. Yes. The tsb called to connect a13 and a15 as seen in the above diagram. Both a13 and a15 have +12v all the time regardless of key position. Its not energized because there is no steady ground. The issue im having is the pcm isn't grounding the relay.