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P1693 codes (SOLO)

290K views 282 replies 102 participants last post by  AvroLancaster 
#1 · (Edited)
I'm going to point out to everyone there is NO WAY to have just a P1693 code present during error code dumping. Yes the P1693 is a companion code and has no really meaning but...

P1693 Code Explained...
https://mopar1973man.com/cummins/ar.../p1693-dtc-detected-in-companion-module-r138/

"This code indicates there is more code present in the other computer" So if the P1693 is in the P PCU that means there is more codes present in the P ECU. So if there is a P1693 in the P ECU that means there is more codes present in the P PCU. Then even in rare cases seeing the P1693 code in both computers pointing out that both computers have codes. But there is NO WAY for the P1693 to be the only codes present during error code dump. It's totally impossible!

The reason I'm posting this is because it seem like everyone is canceling out at the first P DONE thinking its done. WRONG! There is TWO computers in the truck.

P PCU = Powertrain Controller Unit (Passenger side firewall)
P ECU = Engine Controller Unit (Driver side of engine block)

You should always see both P PCU and P ECU displayed and 2 P DONE's in the display.

Best to do all your code reading with a quality OBDII code reader. Yes, you can do the key trick for a poor mans method of checking for codes but only the 2002 model year is reliable for dumping all codes. 98.5 and 99 will not work at all. 2000 and 2001 are a 50/50 mix that you might get just the PCM with just a P1693 or see both the PCM and ECM. Hence where the P1693 Code problem stems from. What happens is the key trick will dump P1693 and then flip back to the odometer. So just best to use that quality OBDII code reader.

Now the other thing is a lot of people are getting error code from OBDII sites or from manuals with the scanners. I'll point out that any code over P1000 is a manufacture specific code that only applies to the that make and model of vehicle so please refer to a proper Factory service manual and get the proper codes. Still always best to refer to my code list with just the error numbers. This way you can get the proper diagnostic information for your problem.

The updated error code and diagnostic information...
https://mopar1973man.com/cummins/ar...generation_50/51_engine/obdii-error-codes_94/

This will help us diagnose your problem quickly and properly. :thumbsup:

Updated: 02/08/2016
All links and information is current.
Mopar1973Man

 
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#2 ·
Hey Mike. Good post, I got a question, what if you get a code that clears itself after a few key cycles, will the 1693 still be there untill cleared?
 
#3 · (Edited)
Once again the P1693 code cannot exist by itself. So if the problem code is gone so is the P1693 code too.

Also take notice the P1693 code NEVER shows up on a hand scanner either it ONLY displayed in the odometer window.

Like this posts...
http://www.cumminsforum.com/forum/9...1-cummins-dead-but-maybe-not.html#post1488367

http://www.cumminsforum.com/forum/98-5-02-powertrain/139611-fuel-derating-2000rpm.html#post1497402

It gets old... You find out everyone is shutting the key off at the 1st P DONE... :banghead:
 
#252 ·
got this code today using my hand held scanner and i cant seem to access the video of yours to see how to read the pcm and ecm to see what the actual problem is
 
#4 ·
BUMPING TO TOP... :thumbsup:
 
#5 ·
Moparman I got one for you, I check my codes with the key trick and was getting a 1693 p-done then back to the trip, I have never gotten more then one p-done before it goes back to the trip, just went out and checked it and the 1693 is gone but I still only get one p-done before it goes back to the trip. am I doing something wrong or worse yet is my truck doing something wrong? One more thing that I would like to pick your brain about, My abs and break lights are on and have been for a few hundred miles but in the last few days they started blinking and when breaking sometimes the pedel gets real stiff and feels like the abs system is kicking (surging) on for a sec. then back to normal breaking then back to the abs stiff pedel and so on and so forth. but after driving for a few tens of miles the lights stop blinking and were back to normal breaking till I shut the truck off, when I turn the truck back on the problam starts all over again.:confused013:
 
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#6 ·
You should still see two listings...

1. P PCU = Powertrain Controller Unit
2. P Done
3. P ECU = Engine Controller Unit
4. P Done

Once again refer to the video on this page...
OBD II Error Codes

So if your seeing the first P PCU and the P1693 is present that means the P ECU has the code. (And visa-versa) So you might have to dig out a scan tool like a ScanGauge II or similar and check for the code.

Still in all the P1693 code will NEVER display in a scan tool and the P1693 code cannot exist by itself.

As for the ABS light blinking that could be a speed sensor going south on you ther is 2 sensors on the front axle (left and right) then 1 sensor in the rear. The rear sensor controls the speedometer. The 3 sensor must all match together other than that the ABS/BRAKE lights are tripped and a P0500 code (in the P PCU) so the P1693 code should be in the P ECU. (Thinking out loud)...

For code to self erase must clear 40 engine warm up cycles without the error tripping again. Engine warm up cycle is starting with coolant temps below 140*F and warming up beyond 160*F.
 
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#8 ·
So basically you saying that one of the computers is NOT coming on line to dump codes any longer. Now you going to have to watch and se which computer (P PCU or P ECU). :confused013:
 
#9 · (Edited)
see i'm just as confused as you are. it doesn't say p pcu or p ecu. it just starts flashing codes, says p done, thats it:doh:

i'm guessing that it's gonna be the pcm codes that i'm seeing since it's the tranny codes and speed sensor codes....i dunno why the hell the ecu codes don't flash lol
 
#14 ·
P1694 - No CCD Messages received from ECM Bus communication failure to PCM. (Network between the ECM and PCM is damaged!)

Kind of hard to have a P1693 when the 2 computers cannot talk to each other... :doh:

Read here...
CCD Data Bus
 
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#15 ·
I know you keep saying there is no way to get the P1693 code without another code popping up, but that is what mine is reading.

There is no P PCU or P ECU that flashes, just the code, then Pdone and back to the odometer.
 
#19 ·
Well, I took the truck to have the codes read and I do have the overboost code, which the dealer told me most of these trucks have and not to worry about it, but it doesn't display when the key trick is performed..... oh well I suppose
 
#22 ·
You need to put a gauge on it,to see what kind of boost you are seeing vs what the ecm thinks you have.A scanner will not tell you how to fix the truck only point you in the right direction :buttkick:
 
#30 ·
lol well it's kind of a strange situation... i am about to leave town and i didn't know about the two p dones i will make sure to check them when i'm back but i'd like to know if clearing it will put me back to normal cuz it ain't running like it first was when i installed the switch?
 
#33 ·
Like I point out in my orignal post...

P-PCU -> P1693 -> P Done -> This is pointing towards the problem being there is codes present in the ECM.

P-ECU

P0236 Map Sensor Too High Too Long Problem detected in turbocharger wastegate
P0237 Map Sensor Voltage Too Low MAP sensor voltage input below the minimum acceptable voltage
P0217 Decreased Engine Performance Due To Engine Overheat Condition Engine overheating. ECM will derate engine performance

P Done
 
#35 ·
This thread def needs stickied!!! But I still do not get the P Done twice or the other two P's. I'm going to experiment with my dads cummins, as well as my buddie's and see what I can come up with concerning there P's...
 
#39 ·
Basically is a function of the staff here at CF.com. If a thread has a lot of good information and write up in it. Then if many people request it to be sticky then the staf will throw a switch to cause the thread to stay on top... :thumbsup:

Sorry it nothing you can do to control it...
 
#40 ·
I feel I need to add this. Not to set people off but to try to help.

I just went to check out a 2000 24v. First thing I checked was the codes. Well guess what, P DONE then back to odometer. I have an 02 that shows both so I knew what to look for and it surprised me when it didn't.

My assumption is this, in 2000 they started the key trick allowing to check codes. Now people with 01's some say they show both some say they only show 1 P DONE. Now wasn't there a year split in 01 giving us the 01.5's?

I'm going to say and I'll ask my dodge mech to confirm (he know's a lot more than the average guy that works there) I think from 00-01 it only shows the one computer and that's the one that comes up with the P1693 saying they need a scanner to find out what the real code is. Then in 01.5 they added in the other computer to the scan allowing the codes to come up with the 2 P DONE's. This is why I feel some say they only get one or only get the P1693 and then back to the odometer.

This is just a theory but I think it fits. :S:
 
#41 ·
It maybe possible? :confused013:

But how about this...

A guy called me asking about a P1693 on a 1998.5 and he used 2 scanner so far (SuperChips and Generic OBD II). Both show the same... :confused013:

This is more common that you think... This is using a actual scanner and not a key trick which does not work on the 98 or 99...
 
#42 ·
I was thinking only towards the key trick results. When you scan with an actual scanner it will pull from both computers but I think in 2000-2001.5 it only pulls from the one, which I think is the ECU since it's the first that comes up on the later years.
 
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