Mopar1973Man

This might help but I can't see the style of plug nor where the wires are going.

You need to talk to @Auto Computer Specialist . They can test your wiring harness for issues and repair it. They can test and repair both the PCM and ECM.

No. The P1688 means the VP44 PSG is no longer functional. The P1689 means the PSG is unable to communicate because a of the P1688 code The P0230 means the voltage / current of the lift pump is out of range. Lift pump is most likely bad or wiring issue.

I was born and raised in LA California. After having things stolen from my home, my car broken into multiple times. Then dealing with the traffic and other issues down there I bailed out to Idaho with my family back in 1990. I don't like even Lewiston or Boise because they are too big of a city really to live in either. I'm way better off staying put right here in Idaho where I'm at. Less dumb- drivers, less theft problems, less taxes, less cost of living, etc. I didn't have a choice of where I was born or living when I was young but now I know the truth and don't want any of the current big city issue. @JAG1 I know you struggle with being outside of Proland, OR.

No. Think a second. How do farmer plant fields? Diesel Tractor. How does the crop get to market? Diesel Semi-truck. How does the store get food on the shelves? Employees, with either gas or diesel powered vehicles. It has zero to do with population but more to do with Biden's desire to shut down all petroleum production. So since fuel is 6.00 a gallon for diesel and figure a single tank on a semi-truck could be 100 gallons that is $600 a tank for fuel. Consider the farm tractors what it takes for running them through the fields to havest or plant said crops. Prices must go up. Like myself I had to change prices of everything I'm doing to stay profitable. Heck with price a fuel I'm now charging $3 a mile to travel to jobs period no questions asked because fuel is so expensive. It takes 180 to 200 dollars to fill Thor now. Use to be just 80 to 90 dollars to fill up now its doubled. Population just means the oil companies are making HUGE profits because of because the opulation needs to pay there bills and working as much as possible and that means travel to and from work. Again population is just the multiplier of the profits that oil company are grining and enjoying Biden's push for the Green New Deal. Nothing green in it for us but the oil companies.

This is why I DO NOT live in a city and hate to be in the city. People are stupid and don't give a crap. Thankfully I'm back home in West Central Idaho.

Still in all if there is a P1688 code that is not clearing hot wire test won't do much being the PSG unit is damaged. Can't fire fuel if the PSG is brain dead.

As for the P1688... Basically the VP44 is dead... At this point the rest of the codes don't count because the PSG unit on the injection pump is shot. I would consider the replacement of the injection pump to insure you have a good PSG unit and don't cheap out. Make sure to buy a pump from a certified Bosch rebuilder or dealer that sells certified Bosh pumps. Like @dieselautopower is the go to spot for a VP44. Also I would highly suggest W-T ground wire mod being that the P1688 is typically from the AC noise issues and bad ground wiring on ECM and VP44.

Welcome to the family... You came to the right place there is enough "gear heads" to keep things moving forward and solve the problems you got.

I've got to look into the photo module on the server it does not seem to see which way is up in the photo. Yup we found a excellent camping spot. Tuck away from the main road. Very peaceful place. This camping trip was a well needed trip. a lot of things had happened during this trip. First off we made a trip over to Warren, ID and visited the old mining town and had a bit of lunch time snack. Wondering the dirt roads. Even picked up a bit of firewood. Now that we had a day of rest playing in Warren. We did wonder the roads a bit more to the north and it get pretty rough out there. One of these day in the sum,er when weather is better we will make the loop from Warren, ID to Yellow Pine, ID which happens to be the most remote town in Idaho. Yeah I've been to Yellow Pine but its been years ago. Oh look close there is a old tree stuimp under my truck... Now on the return to the RV that night we sat down and kind of had a simple dinner of sandwiches. Then we sat down started talking business a bit that night. Crazy part we came up with a business plan for the website and there is going to be major changes and improvements. Matter of fact it last til 1am in the morning just chatting and designing the future of Mopar1973Man.Com. So fair warning there is more to come. A LOT MORE! Again I've got to give huge thanks to @Honey Badger for the ideas and effort she is putting into this whole business.

EGR cooler I would of told you to freeze plug both ends of the exhaust passage. That way the cooler does rupture. Works good on our 6.0L Ford Fire truck.

Welcome to the family here. There is no such thing as stupid or dumb questions. Everyone attempts to help and teach each other the knowledge we glean from each case or problems. I might be a mechanic but I'm a self taught on the Cummins diesels. This community started as a small collection of notes and info that mushroomed into what you see today. As for the W-T ground wire mod is super simple and can be done in about 2 hours.

I ran down in Mojave Valley AZ in 110 to 120F. IAT never exceeded 140F. Not even a EGT issue there. Hauled the RV down was kind of stuck the with George Floyd riots. Using a BHAF. Regardless of the cold air intake the intercooler does more work cooling the air than a cold air intake.

Finally I got you all looking past the Cool Factor into the design factor and getting your truck set up for proper gearing ratio then you notice power gain and efficiency improvements. On other member @Sycostang67 took my advise and now also change because cool factor was the source of EGT problem changed tires down and gain back the performance.

Huge difference in stress on the transmission. You forget your 4th gear is 0.68:1 compared to my 5 speed of 0.75:1. Plus the final to the ground on 3.42:1 so yeah EGTs and transmission issues are going to happen. Optimal is close to 3.73:1 to the ground. You have two things pushing the gear ratio lower. Hence the starting problem of EGTs. Next will be transmission issues. 65 MPH should be very close to 2,000 RPM optimally which I know your way down near 1,600 RPM which is way too low adding stress to both engine (EGTs) and transmission (failure). Very common issue I see every day. But people just like the cool factor, but don't understand just 1 size up (31 to 32 inch) make such a huge difference. Just like I'm just one size down (31 to 30 inch) and way different results. Just only 1 inch can make or break it... seriously! My was purchased new with 265's but opted for the 245's for final ratio improvements. Yes my door sticker is the same 245/75 R16.

I've seen all kinds of Redneck fixes and they all suck. Not that it can't be fixed but why do half work? If you damage the yoke then replace it. Like my last screw up i was changing the rear most u-joint on Beast and tore up the one ear on the yoke. I paid 660 dollars to have that yoke cut off a new yoke welded in. Spun balanced and new carrier bearing. Now that's doing it right might cost you but no welding of bearing caps.

Newsmax was saying Biden is requesting a increase in production of fuel problem is producing with foreign oil.

Another tidbit cold air intakes actually don't help. Warm air promotes easier ignition of fuel. Optimal intake temp is 100 to 140°F. Colder air tends to retard ignition timing. Even towing with 100 to 140 intake temps has no impact on EGTs. Below 80°F the ECM stacks on additional 3 to 4 degrees timing advancement which fouls the timing as too advanced (without Quad). This way I'm running BHAF vs any cold air intake. Like my youtube of 55 MPH on flat ground I'm only like 450°F EGTs. Just using my truck as a good design example here not trying to hijack.

Mechanical pump are only 15% efficient being pumps as the lobe rolls away. Another reason I will not suggest a mechanic stock pump. Also most running p-pump had to upgrade to AirDog or similar to get thevolume that the stock mechanical can't do.

Diesel fuel just crossed 6.00 dollars a gallon here in Idaho. Washington state in Seattle was 6.279 a gallon just last week.

7 x0.010 injectors from DAP custom pop pressure at 320 bar. Then running stock HX35W turbo. Might look at my economy tune, it designed around the MPG so it not producing serious power till 20 PSI of boost. This is pretty mild on the bottom end. Even if you run 245/75 R16 tires it takes a lot of stress of the transmission and driveline being the final ratio is 3.69:1. One of the biggest killers for 47RE transmission is oversize tires. Oversized tires might look cool but but bad final ratios put huge amount of stress on the transmission. Example: 37 inch tires on 3.55 gears will produce a final ratio of 3.00:1. For sure a transmission killer. Keep in mind I've managed to snap the main shaft on NV4500 with Edge Comp and +75 HP injectors. Just remember I went to Cally hauling my 31 foot RV and still running my stock HX35W turbo. No EGT issues hauling 17,500 pounds. Went with @IBMobile and @JAG1. Then just went to Everett WA with @Honey Badger and pulled 300 miles across Washington state and barely burn a quarter tank. (Seattle,WA to Idaho state line)

Yeah not to bad. Just got to dive in and fix the issues one at a time. At least it got cooling fans for now. Like the axle stub that isn't too bad. Smaller version of the truck axle. What does kind of upset me is people making false claims of big failures when it simple shade tree repairs. Now it just a matter of getting funds together on honey badger side and for me to install said parts. Even worse is fixing a shade tree repair that welding parts together.

Well I had a run to head up and look at @Honey Badger Mom's Jeep nothing really wrong just battery is weak security system tripping. Then locking out the ignition. Just unlock the drivers door with the key and its disarmed again as long as you dont leave the key in the vehicle. There was a family member that told her the catalytic converter was bad, nope there is a hole in the pipe near the catalytic converter. Misinformed and lead to believe big money repairs. We took a break and ran with @Honey Badger jeep out Red Ridge to pick some mushrooms. Her jeep started to heat up. Fan weren't working. Her past boyfriend hacked up the entire fan circuit to make a wiring nightmare. Did a few modification on the dirt road and presto had at least key on fans. Drove back to her place. Now I parked right next to Thor and started working. Test light chr king fuses, found the factory fan plug. Tested got signal. Now I know I need a new pigtail. In the meantime to keep it going added a ring terminal for the ground to negative post. +12V I tucked in on the fan relay on the 87 pin. Fired it up and let idle it would get to the 210°F mark and kick the fan on drop to right about 200°F and shut off. Perfect. Found a power steering hose bleeding through the jacket of the hose slowly. She mention some welding on axle. Found it someone changed the wheel joint and crushed the outer stub some so the clip would fit so they welded the bearing caps in. Now ive got to pull that axle out cut the turnion out and discard the outer stub and replace the wheel joint. Rear shocks are toast. Really she has been misinformed about the amount of work and repairs like needing a whole new front differential.

@Dynamic is a good guy to ask those questions with him.

Let me tag her @Honey Badger