Another Total Power Loss While Driving

[igorek84]

Hey everyone - my first post here. I just experience a total power loss while driving my 2023 Jeep Wrangler Willys 3.6L a couple of days ago. I was at a stop sign, hit the gas, the Jeep jerked a little threw a check engine light and a flashing "D" light for drive I'm assuming, then shortly after as I was making a left hand turn, everything died. Then I coasted over to the side of the road. When I say everything died, I mean the engine shut off and all of the electronics inside. Not even the hazard lights, power locks, horn, nothing works.

This is my first Jeep and from my research I already can tell that the previous owner (I'm the second owner) did an auxiliary battery bypass as the fuse array is wired differently than factory. For instance, the N1 wire is sitting on the N2 post of the PDC. Also, I'm not seeing the second ground wire meant for the auxiliary battery attached at the negative battery terminal. The F42 fuse is also not there. I assume the auxiliary battery has been removed and bypassed.

What I've done so far. I've tested the negative battery terminal to G200 inner fender post and negative battery terminal to an exposed post on the engine with a multimeter, both had continuity. Then I checked all of the posts on the main fuse array. All 4 are getting power, including the last one being N8. I also pulled out the fuse array and tested it for continuity between B+ and the rest of the contacts, all checked out. I assume that's not the issue. Next, I checked the fuses inside the PDC by checking them for voltage. Only F03 is showing 12.6v, all the rest are either 2.67v or 0v. Could this mean I have a faulty PDC? Just to completely rule out the battery, I took it to both Advance Auto and AutoZone and both places cleared it as a good battery. I also checked the green and white star blocks behind the glove box, everything looks good visually. Everything sits tight and there is no sign of water damage or anything.

I did order a spare fuse array just to eliminate that completely, but I don't think that's the issue. I'm looking at my PDC part number and it's 68520854AA. I can't find it on the mopar parts store. They only have one ending in 51AA. Is that another thing that was potentially swapped by the previous owner? I'm going to attach several pictures I've taken, hoping someone can help on what to try next.

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[dank8307]

68520854AA is for 3.6L eTorque. 68520851AA is for 3.6L with the regular ESS.

If 68520854AA is the actual PDC which came with the vehicle, it's extremely weird that the previous owner would have performed an aux battery bypass on an eTorque model. If I remember correctly, eTorque models don't come with fuse F42, as well as the extra cable for the 12V aux battery since it doesn't exist. Just to try something out, move the N1 to where it's supposed to be.

@AllMoparParts.com please correct me if I'm wrong about the part numbers.

 

[alphawolff]

You engaged stop start, and upon engine restart the z-case fuse blew. The aux battery, which is now running the entire vehicle's electronics by itself without being charged, died almost immediately.

The z-case fuse blowing in this very specific scenario is *extremely* common.


You do not need a PDC. You need a Z-case fuse and an aux battery. For future reference the system goes PRIMARY->N2/N3/N4/N5/N6->PCR->AUX->N1(n1 is the actual PDC power input). N3 goes to the PCR.




edit; just realized you don't have an aux battery (e-torque?) anyway, your PDC eyelets are also jumbled/missing. N1 is completely empty despite having witness marks. This is your issue, move that eyelet down one. Double check there isn't an eyelet stuffed down there somewhere, I don't recall the e-torque eyelet layout off the top of my head, but that bottom one is on the wrong post. The fuse is effectively just sitting on top of the PDC contact without being bolted down.

move it here:

You can also leave it where it is and just put a nut there, that works too since it's just a bridge.

 

[igorek84]

Thank you both!

@dank8307 Looking at the original window sticker, this appears to be a VVT eTorque engine with stop/start. That means part number 68520851AA is not compatible. And yes, the one I have doesn't have an F42 fuse, or even fuse blades inside the socket. I think it was never there.

@alphawolff I think you're onto something! The jeep's been wired this way for over a year, the time I've owned it so I didn't want to mess with it. But I did have another similar shut down 3 months back. Back then I physically pushed down on all the fuses and relays (some felt loose), then the jeep came back to life and I was able to drive away. Perhaps it made contact with the N1 post when I did that restoring the bridge connection. I think you're right in saying it's missing that bridge contact and the other half of the PDC is effectively not getting any power. I sure hope that all I need is a nut!

I'm still wondering why the previous owner moved the N1 eyelet onto the N2 post. Is this common or just a mistake? Wondering if this was a quick fix for something in the past. Does anyone have a picture or a wiring diagram for an eTorque 3.6L PDC?

 

[igorek84]

I just found this searching online. I believe this is from a eTorque model also because it only has 4 eyelets, missing the F42 fuse, and missing the N7 alternator eyelet. All suggesting that it's an eTorque model like mine. I can see that they have N1 eyelet on an N1 post and N2 is simply secured by a bolt. I will try this today and report back. Hopefully it was a mistake by the previous owner/dealer. Thanks guys!

 

[igorek84]

Reporting back that this fixed it. I moved N1 eyelet back to N1 post, and secured N2 post with a nut. The jeep is happy again. Special thanks to @alphawolff for identifying the issue.

 

[AllMoparParts.com]

68520854AA is for 3.6L eTorque. 68520851AA is for 3.6L with the regular ESS.

If 68520854AA is the actual PDC which came with the vehicle, it's extremely weird that the previous owner would have performed an aux battery bypass on an eTorque model. If I remember correctly, eTorque models don't come with fuse F42, as well as the extra cable for the 12V aux battery since it doesn't exist. Just to try something out, move the N1 to where it's supposed to be.

@AllMoparParts.com please correct me if I'm wrong about the part numbers.

2018 JL 3.6 W/ESS current part # is 68298936AD

Your # is 2022-2023

Please let me know if you have any other questions at this time.

Thank you,
- Benny

 

[THAW]

Reporting back that this fixed it. I moved N1 eyelet back to N1 post, and secured N2 post with a nut. The jeep is happy again. Special thanks to @alphawolff for identifying the issue.

While you're correct the cable was on N1 from factory, in the eTorque N1 and N2 are connected by a shunt so it really shouldn't matter. Your issue was the missing nut that created a loose connection at N1 which is the connection to the PDC (i.e. the fuse box and the majority of Jeep electronics) from the power sources (battery and BSG/PPU).

 

[alphawolff]

While you're correct the cable was on N1 from factory, in the eTorque N1 and N2 are connected by a shunt so it really shouldn't matter. Your issue was the missing bolt that created a loose connection at N1 which is the connection to the PDC (i.e. the fuse box and the majority of Jeep electronics) from the power sources (battery and BSG/PPU).

the lead should be on n1. you don't even need a nut on n2 as it's a hard connection

 

[THAW]

the lead should be on n1. you don't even need a nut on n2 as it's a hard connection

Respectfully, I disagree; the Z Case Fuse Array needs to be clamped to N2 with a nut.

Yes, the cable/connector should be on N1. But swapping the N1 captured-nut cable connector and the N2 nut makes no electrical difference. An altogether missing nut creates a loose connection; if it's missing at N1 the Jeep/PDC can lose power, if it's missing at N2 the battery can lose PPU charging.

OP needs a nut on N2 (after moving the cable/connector to N1).

 

[alphawolff]

Respectfully, I disagree; the Z Case Fuse Array needs to be clamped to N2 with a nut.

Yes, the cable/connector should be on N1. But swapping the N1 captured-nut cable connector and the N2 nut makes no electrical difference. An altogether missing nut creates a loose connection; if it's missing at N1 the Jeep/PDC can lose power, if it's missing at N2 the battery can lose PPU charging.

OP needs a nut on N2 (after moving the cable/connector to N1).

n1 and n2 are connected via a metal bridge, there aren't any contacts or leads coming off n2. n1 however needs to physically touch the PDC contacts underneath it. you don't need any type of nut on n2, it does nothing other than keep it snug against the PDC post which doesn't have any type of impact on performance due to no power flow to a lead. it just goes right down through the fuse.

 

[THAW]

n1 and n2 are connected via a metal bridge, there aren't any contacts or leads coming off n2. n1 however needs to physically touch the PDC contacts underneath it. you don't need any type of nut on n2, it does nothing other than keep it snug against the PDC post which doesn't have any type of impact on performance due to no power flow to a lead. it just goes right down through the fuse.

The N2 fuse needs to make firm contact with the shunt that connects N2 to N1, since the Fuse Array is the bus connecting N1/N2 to the PPU at N8 (and not insignificantly the RAD FAN at N5). There's a nut form factory, as shown by OP in an image he found:

 

[alphawolff]

The N2 fuse needs to make firm contact with the shunt that connects N2 to N1, since the Fuse Array is the bus connecting N1/N2 to the PPU at N8 (and not insignificantly the RAD FAN at N5). There's a nut form factory, as shown by OP in an image he found:

 

[THAW]

That's the N7 and N8 end - the alternator or PPU, respectively.

Here's the eTorque N1/N2:

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