Strange electrical issue

[petersonj]

Power mirrors - INOP - Fuse 13

Power mirrors come from Fuse #12. Power door locks come from Fuse #13. What is interesting is that the power door locks use C203 which is the same connector that supplies power to the dome lights, power mirrors, and cargo lights. @RDMueller said, "in my case both wires going to the dome light are dead." This tells me that there is a power supply problem and at this point would not involve the Central Timer Module. Connector 203 is the one thing that is in common with power door locks, power mirrors, dome light, and cargo light.

- John

 

[petersonj]

Good to hear that it is solved - we definitely want to hear the solution.

- John

 

[RDMueller]

All along I thought there was a good chance this was something simple. The problem ends up being with so many places to look, it’s like finding a needle in a haystack! I finally decided it was time to start taking things apart and just look for obvious problems like broken or chafed wires, loose connections, etc. An obvious place to start was the CTM or back of the JB. Took off the panel below the steering column and started looking around, almost immediately saw this cannon plug partially out. Snapped it back into place, immediately noticed the dome light and map lights on! Checked other items - all working. It does appear that the locking mechanism (the black bracket on the bottom) is broken and not engaging properly allowing the plug to just work its way out over time.

 

[RDMueller]

I want to thank everyone, especially Bruce and John, I know you guys spent a bunch of time looking at the FSM diagrams and trying to isolate what was going on here, and posting on the thread. I really appreciate your time and help! I was really worried that I’d be pulling the dash for the 3rd time (1st time heater core, 2nd time evap replacement and replacing the cracked dash). So glad in the end it was something so easily accessible!

 

[brucejohnson]

Power mirrors come from Fuse #12. Power door locks come from Fuse #13. What is interesting is that the power door locks use C203 which is the same connector that supplies power to the dome lights, power mirrors, and cargo lights. @RDMueller said, "in my case both wires going to the dome light are dead." This tells me that there is a power supply problem and at this point would not involve the Central Timer Module. Connector 203 is the one thing that is in common with power door locks, power mirrors, dome light, and cargo light.

- John

Yep. Yesterday's mapping...and there's C203 (right side) in common on the first three of the many issues listed. Snake bite!!!
Thanks John and RDMueller for sharing.

 

[brucejohnson]

Power mirrors come from Fuse #12. Power door locks come from Fuse #13. What is interesting is that the power door locks use C203 which is the same connector that supplies power to the dome lights, power mirrors, and cargo lights. @RDMueller said, "in my case both wires going to the dome light are dead." This tells me that there is a power supply problem and at this point would not involve the Central Timer Module. Connector 203 is the one thing that is in common with power door locks, power mirrors, dome light, and cargo light.

- John

I'm a con-fused dork...

 

[brucejohnson]

Connector 203 is the one thing that is in common with power door locks, power mirrors, dome light, and cargo light.

And the Standard Audio (radio) front and rear speakers.
8W-47-5 and -6.

 

[RDMueller]

So here’s a question I still have for future reference. Let’s say using the diagrams and mapping things out, you come to the conclusion that C203 for example is a common point and you want to check that out. You can see it on the diagrams, but how do you determine where C203 is physically located on the vehicle? I’m sure there must be somewhere in the FSM where it has a list of connectors and their locations, but I haven’t found it!

 

[brucejohnson]

So here’s a question I still have for future reference. Let’s say using the diagrams and mapping things out, you come to the conclusion that C203 for example is a common point and you want to check that out. You can see it on the diagrams, but how do you determine where C203 is physically located on the vehicle? I’m sure there must be somewhere in the FSM where it has a list of connectors and their locations, but I haven’t found it!

Yes. There is a section devoted to location as well as connector pinouts, factory splices and ground points, etc..
In the 2002 book they are located after the schematics. Starting at 8W-70-1 for splices, 8W-80-1 for Connector pinouts, etc..

 

[petersonj]

Bruce, click on "8W Wiring" in the Table of Contents. Then select "Connector/Ground/Splice Location". That will take you to 8W-91-1. From there you can find C203 (Fig. 30) or any other connector, ground, or splice.

Appreciate your help with this particular challenge (it was a brain teaser). And @RDMueller , good job being patient and methodical.

I am editing this post because I just realized that RDMueller was asking the question.

- John

 

[brucejohnson]

Oops...didn't take...deleted.

 

[brucejohnson]

Bruce, click on "8W Wiring" in the Table of Contents. Then select "Connector/Ground/Splice Location". That will take you to 8W-91-1. From there you can find C203 (Fig. 30) or any other connector, ground, or splice.

Appreciate your help with this particular challenge (it was a brain teaser). And @RDMueller , good job being patient and methodical.

I am editing this post because I just realized that RDMueller was asking the question.

- John

View attachment 137804

View attachment 137805

"Click" like in take a picture?

This picture is to answer to RDMueller's question.

 

[RDMueller]

Yes it definitely was a brain teaser!

 

[brucejohnson]

Oh the challenges to get a photo posted...

Here's an example showing the picture of the C203 location (lower right) along with all the bookmarks...

 

[brucejohnson]

All along I thought there was a good chance this was something simple. The problem ends up being with so many places to look, it’s like finding a needle in a haystack! I finally decided it was time to start taking things apart and just look for obvious problems like broken or chafed wires, loose connections, etc. An obvious place to start was the CTM or back of the JB. Took off the panel below the steering column and started looking around, almost immediately saw this cannon plug partially out. Snapped it back into place, immediately noticed the dome light and map lights on! Checked other items - all working. It does appear that the locking mechanism (the black bracket on the bottom) is broken and not engaging properly allowing the plug to just work its way out over time.

View attachment 137802 View attachment 137801

By the way...Looks nice and clean under the dash. Undoubtedly one sweet, pampered truck.

 

[Topzide]

@RDMueller, Did you put a cable tie on that connector? Yes, electrical issues will make you loose your hair quicker the normal! This is what this forum is all about, helping others with their trucks! I have a Haynes manual for my '01 1500 and looked at the wiring schematics and wouldn't have been any help. The first thing I did when I got the 3500 was to get factory manual! It's helped me solve a few issues and plan for adding goodies! Always willing to help where I can and especially on a 2014 since have FSM!

 

[BigPapa]

Did you put a cable tie on that connector?

It has a cam-lock lever to pull it tight and a locking tab on the lever. Somebody had to try to not fully connect that one at one time or other.

 

[RDMueller]

By the way...Looks nice and clean under the dash. Undoubtedly one sweet, pampered truck.

Thanks! And yes, for its age and mileage (330k), it is in great shape and has been a really good truck for me. Very dependable, never left me stranded and I feel very easy to work on. The only time I can remember having it in a shop was to rebuild the NV4500 after losing 5th about 13 years ago. Everything else that has come up I’ve been able to handle myself, with the help of this forum! Early on I addressed the factory shortcomings adding a fuel pressure gauge and raptor 100 lift pump, so I’m still on the original VP44. As I previously mentioned, I’ve had the dash out twice, first for the heater core and then a few years later for the evap. That job was probably the one I was most concerned with going in, but I found it to be actually pretty easy. Other than that, it has just been scheduled maintenance or wear items like brakes. I did recently replace all 4 control arms due to the ball joints needing replacement, but at 330k I see that as a wear item to be honest. Even the paint is still in remarkably good shape. This electrical problem is the first time thoughts of, “wow, I wonder if it’s time to start considering…” actually crept into my mind! And in the end it was just a loose connector! So it looks like good ole Silver Truck will live on and may very well get his 500k badge some day.

 

[RDMueller]

@RDMueller, Did you put a cable tie on that connector? Yes, electrical issues will make you loose your hair quicker the normal! This is what this forum is all about, helping others with their trucks! I have a Haynes manual for my '01 1500 and looked at the wiring schematics and wouldn't have been any help. The first thing I did when I got the 3500 was to get factory manual! It's helped me solve a few issues and plan for adding goodies! Always willing to help where I can and especially on a 2014 since have FSM!

No, it is snapped into place and locked properly now. I probably didn’t get it locked after the last time I had the dash out.

 

[RDMueller]

It has a cam-lock lever to pull it tight and a locking tab on the lever. Somebody had to try to not fully connect that one at one time or other.

Yeah, that must be the black part. I think last time I put it together after having the dash out, I didn’t fully understand how to properly lock it. Those connectors always seem to give me fits, mainly getting them apart because it seems like every one is a slightly different design and you are usually working in tight quarters and can hardly see what you are doing. But I’m sure I have it right now!