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Discussion Starter · #1 ·
Hi all,

First off, sorry for the lengthy post. I am just so frustrated as this mechanic isn't trying to offer any kind of help as its been a month already where the Jeep has been sitting. Before this, although it had the two codes it was running FINE without any of these issues.

I have a 2012 Jeep Grand Cherokee SRT8 6.4l engine (6.4l engine). I recently had an independent mechanic working on my vehicle after I noticed I had the following codes: After investigating we noticed BOTH the 3 wire Engine oil pressure sensor harness was damaged/eaten by possibly a racoon. We cut the harness, changed it out and the "OIL PRESSURE" codes disappeared. It ran fine for a whole month with just the OIL TEMPERATURE sensor code remaining.

About a month later we then looked into the oil temperature sensor harness (2 wire) and noticed it was damaged. He went ahead and changed out the harness however I did not see exactly what happened as I was sitting in the vehicle getting ready to Start the vehicle.

After connecting the last harness, he asked me to start the car... I got nothing. He thought the battery was dead and proceeded to connect jumper cables and tells me to try again. I heard a loud "click" (not sure if it was a spark) and a red lightning bolt on the dashboard... I asked the mechanic what was that? and explained to him that I am seeing a red lightning bolt on the dash that I have never seen before... he claims he forgot to connect a wire. He makes whatever changes and tells me to start again. I start and the car starts fine without any codes.
On my way home, less than 5 miles away... the lightning bolt comes back on the dash and the car starts to lose, the check engine light is back on as well. I then scan the vehicle for codes and now have the following codes:

  • RED LIGHTNING BOLT ON DASH AS SOON AS CAR IS TURNED ON (engine off or on)
  • P0523 - Engine Oil Pressure Sensor / Switch High
  • P0340 - Camshaft position sensor A circuit bank 1 or single sensor
  • P0198 - Engine Oil Temperature Sensor High
  • P0108 - Manifold Absolute Pressure Barometric Pressure circuit high
  • P0471 - Exhaust pressure sensor A circuit Range / Performance
  • P0473 - Exhaust Pressure Sensor A Circuit High

(after rewiring both harnesses that he installed, I'm still left with three codes) P0473, P0108, P0523

I'm wondering what really happened under the hood before the car was started? Is it possible something shorted out? Is it possible he reversed polarity while trying to jump the vehicle? He claims it would have blown a fuse before messing up the computer... but at this point I am not sure . Prior to this I never had ANY electrical issues with this car so I doubt it's something that just decided to show up exactly when wires were being replaced.

Any recommendations would be greatly appreciated!
 

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A loud click would most likely be the starter solenoid engaging. I would not describe a spark/arc as a click, it's a very distinct snap/crack sound.

Another possibility is the throttle valve opening/shutting sound, but that would not be very loud.

Accidentally getting the polarity wrong would definitely blow fuses, so if you were able to start the car and get going without changing any, I do not think it's likely that such a mixup was made.

Since a vermin chewed up wires, the most likely cause for various codes is that there still are broken harnesses in the engine bay. They may have shifted when repairs were made to the most obviously broken ones, and then shorted out or lost contact.
 

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Discussion Starter · #3 ·
A loud click would most likely be the starter solenoid engaging. I would not describe a spark/arc as a click, it's a very distinct snap/crack sound.

Another possibility is the throttle valve opening/shutting sound, but that would not be very loud.

Accidentally getting the polarity wrong would definitely blow fuses, so if you were able to start the car and get going without changing any, I do not think it's likely that such a mixup was made.

Since a vermin chewed up wires, the most likely cause for various codes is that there still are broken harnesses in the engine bay. They may have shifted when repairs were made to the most obviously broken ones, and then shorted out or lost contact.

thanks For the response. The only sensor we changed was the oil pressure sensor I believe which was one of those cheap after market parts. Is it possible the sensor has a short perhaps and causing all of these codes? I had the harness checked from end to end for continuity and everything seems fine.

what’s making me feel like something happened at that moment when trying to start the vehicle was the fact that I saw that red lightning bolt for the first time every as soon as we tried to start the vehicle.

All fuses check out fine, the car does take some time to start (about 20 seconds or so) as if the engine oil pressure sensor is unplugged but eventually it does start up and idles. When you hit the gas sometimes it sounds like it’s losing power.

I’m wondering if it could be the battery? I installed it a year ago… but possible?

appreciate your help.
 

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Discussion Starter · #4 ·
Another thing is a mechanic told me the car is running with the map sensor unplugged that the car shouldn’t run smoothly .. does that add any help to what might be going on? Or is this even true
 

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A long cranking time would suggest fuel delivery problems.

As for the lightning symbol I'm not sure, but I think it's "standard" signal after a failed start.

There are multiple harnesses in the engine bay, were they all checked?

And yes, a poor quality/incompatible/faulty sensor might throw multiple codes.
 

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Lightning is an issue with the electronic throttle control.
If it’s flashing do not drive it. Try unhooking the battery for a half hr. To see if it resets. Check wiring to the throttle body.
Sounds like the car had old codes stored.
Do you have a code reader? If so, clear all codes before you start it.
Hook up ALL sensors. Don’t run the car without the map hooked up!!!


Sent from my iPhone using Tapatalk
 

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Hi all,

First off, sorry for the lengthy post. I am just so frustrated as this mechanic isn't trying to offer any kind of help as its been a month already where the Jeep has been sitting. Before this, although it had the two codes it was running FINE without any of these issues.

I have a 2012 Jeep Grand Cherokee SRT8 6.4l engine (6.4l engine). I recently had an independent mechanic working on my vehicle after I noticed I had the following codes: After investigating we noticed BOTH the 3 wire Engine oil pressure sensor harness was damaged/eaten by possibly a racoon. We cut the harness, changed it out and the "OIL PRESSURE" codes disappeared. It ran fine for a whole month with just the OIL TEMPERATURE sensor code remaining.

About a month later we then looked into the oil temperature sensor harness (2 wire) and noticed it was damaged. He went ahead and changed out the harness however I did not see exactly what happened as I was sitting in the vehicle getting ready to Start the vehicle.

After connecting the last harness, he asked me to start the car... I got nothing. He thought the battery was dead and proceeded to connect jumper cables and tells me to try again. I heard a loud "click" (not sure if it was a spark) and a red lightning bolt on the dashboard... I asked the mechanic what was that? and explained to him that I am seeing a red lightning bolt on the dash that I have never seen before... he claims he forgot to connect a wire. He makes whatever changes and tells me to start again. I start and the car starts fine without any codes.
On my way home, less than 5 miles away... the lightning bolt comes back on the dash and the car starts to lose, the check engine light is back on as well. I then scan the vehicle for codes and now have the following codes:

  • RED LIGHTNING BOLT ON DASH AS SOON AS CAR IS TURNED ON (engine off or on)
  • P0523 - Engine Oil Pressure Sensor / Switch High
  • P0340 - Camshaft position sensor A circuit bank 1 or single sensor
  • P0198 - Engine Oil Temperature Sensor High
  • P0108 - Manifold Absolute Pressure Barometric Pressure circuit high
  • P0471 - Exhaust pressure sensor A circuit Range / Performance
  • P0473 - Exhaust Pressure Sensor A Circuit High

(after rewiring both harnesses that he installed, I'm still left with three codes) P0473, P0108, P0523

I'm wondering what really happened under the hood before the car was started? Is it possible something shorted out? Is it possible he reversed polarity while trying to jump the vehicle? He claims it would have blown a fuse before messing up the computer... but at this point I am not sure . Prior to this I never had ANY electrical issues with this car so I doubt it's something that just decided to show up exactly when wires were being replaced.

Any recommendations would be greatly appreciated!
I recommend you take it to a Jeep dealership and have it repaired. It would be difficult to have a forum reader diagnose it from afar. Your problem shouldn’t be too difficult to diagnose. The dealership diagnostic computer can quickly run system test to isolate the problem. Modern days automobiles have complicated electronic control units that quickly scan different subsystems for specific readings prior to issuing the start command. If the oil pressure sensor doesn’t present the proper signal, the ECU wouldn’t issue a start command. But, again, the dealership mechanics could quickly diagnose that problem. Good luck!
 

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I’m not an expert. Maybe the mechanic had something disconnected that was applying power to say a module. There’s a chance that he shorted something. If you didn’t mention the problem you’re having, I would definitely ask him what he forgot to connect to narrow down the problem.
 
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