Hi all...
I chose to write this thread separately because I have a No Cluster Lights - No Crank issue and I'm down to three things: the DTR sensor, the Central Junction Box, or something is triggering the anti-theft (but I think this is unlikely) and I'm trying to isolate the trouble...
This thread is a continuation of another one, with the most recent information at the bottom of it:
https://www.f150online.com/forums/el...ch-lock-2.html

Its a 2006 F-150 STX, 4.6L engine...I had the battery disconnected for about 4 days, and when I connected it to get back to try to diagnose the truck this morning, the cluster lighted up and started right away... I couldn't believe it, so I turned it off, waited ONE minute and the cluster lighted up and started again. I did it a few more separate times, waiting additional minutes between each attempt until the last one was after waiting 5-7 minutes from the previous one, and everything turned out like when the truck was new... I never touched anything on the truck other than the key...

THEN... after starting one last time and allowing it to warm up a few more minutes, I decided to shift into REVERSE and boom... DIED... everything off, no cluster lights, no gauge movement... I turned the key to OFF, removed it, and when I tried again, no lights to the cluster whatsoever, NOTHING more, its like it does not have a battery, and it has been like that for the past few hours.

Could this definitely be a bad DTR sensor??? My OBDII scanner doesn't show any set or pending codes. I don't know what is the main symptom when the DTR sensor goes bad. I thought that when it fails, it will shut down the truck, but when I shift back into PARK, I should get lights at the cluster and be able to start once again...

Maybe some kind of circuit at the junction/fuse box that needs to "rest" for a few days before starting again??? (LOL...I can't believe I wrote that out of desperation)...

Thanks to everyone that is able to share some info...

 

I'm leaning towards a bad fuse box - Central Junction Box. I'm not getting power to the gauge cluster and I'm hearing all sorts of low buzzes/loose ground sounds coming from it when I put the key to the ON or START position. I didn't know these boxes had a circuit board or main board inside, like a computer...

No more for today... I'm open for suggestions and recommendations until I get the final solution to it...

HAPPY THANKSGIVING TO ALL !!!!!!!

 

Well... a few weeks have gone by, I removed the fuse box and had it checked, needed to replace 2 of the internal fuses, but after re-installing it, nothing has changed... still intermittent/fading cluster lights and the buzzing sounds coming from underneath the dash, somewhere between the passenger's side kick panel and the center console, where the radio is. A loose ground maybe???

 

A few things you could check in and at the Central Junction Box (CJB).

1. There are two separate ground points on the body by the CJB. Check them for corrosion, good contact and broken/frayed wires.
2. Remove PCM Power Relay (PPR) and check it for corrosion and proper function.
3. Check fuse F12 which supplies power to the PPR slot #2.
4. Check PPR #2 slot for 12V
5. Check PPR #3 slot for 12V.
6. With the ignition switch on, check the PPR #1 slot for ground.
7. Reinstall the relay (if it tested good), turn on the ignition and check fuses F32, F33 and F34 for power. When the PPR is engaged, it sends power to those 3 fuses. If no or weak power power is present, try swapping out the relay with the Trailer Tow Parking Lamp Relay and test again.

You could also check fuse F28 which supplies the Passive Anti-Theft Transceiver Module

https://fusesdiagram.com/wp-content/...k-kapotnew.jpg

 

Thank you for your reply... I'll get back to check each one of the ground points.
The guy that checked the fuse box said that it is working quite fine regarding all relays and fuses. He replaced the internal fuel pump micro relay and the internal battery micro relay... those two are permanently soldered to the internal computer board of the box... he also placed a sticker on the side of the box so as not to re-open it and marked all fuse spaces that were not used...

There is a cable that comes from underneath the steering column, goes all the way across the dash, underneath the radio, beneath the glove box rail, over the fuse box and goes out through the firewall in the direction of the ECM or battery, have to check it... I agree: the buzzing sounds like a bad ground and/or contact...

Thanks...

 

You still need to do testing while the CJB is hooked up. A wire may be broken or loose that feeds a certain terminal in the CJB and you're not going to know until you physically test to make sure you're getting the ground and power required for a particular circuit or relay.

As for grounds, there's another ground on the back wall the VSM uses that you could also check. You'll have to remove the back rest part of the rear seat to get to it.

I can't think of one cable like that. Are you sure it's not two different cables. Possibly the shifter coming out of the column and going through the firewall behind the dash. Then maybe the radio antenna cable going along the glove box and out the firewall by the battery.

 

Here's what I did and found...:
1. The separate ground points on the body by the CJB... OK
2. Removed PCM Power Relay (PPR) and check it for corrosion and proper function... was OK
3. Check fuse F12 which supplies power to the PPR slot #2... OK
4. Check PPR #2 slot for 12V...OK
5. Check PPR #3 slot for 12V... OK
6. With the ignition switch on, check the PPR #1 slot for ground... could NOT get continuity when grounded... I have to re-check this with some other method...
7. Reinstalled the relay (it tested GOOD) turned on the ignition and checked fuses F32, F33 and F34 for power... F32, F33, F34 had 0.0 V when tested
8. Fuse F28 which supplies the Passive Anti-Theft Transceiver Module showed 1.5-1.7 V

THEN, while looking under the dash for anything strange, I heard a humming/hollow sound coming from underneath/behind where the radio/AC controls are, it sounded like something was "charging", if that word can be used... I stopped what I was doing and voilá... power restored to the cluster. The truck started fine a couple of times, I took a break to have a snack and when I came back and tried to start, I got the same dimming/fading of the cluster lights, they went off again and I have not been able to start it since...
One thing for sure, I'm getting close to ending this nightmare, I'm not quitting on this one... Is there any other method to check for ground on the previous step #6??

Anything else I might be overlooking?? ...and yes, the strange cable going along the glove box is the antenna.

 

F28 also supplies IGN SN to the PCM. Maybe the CJB is dropping the voltage on F28 to 1.5V. I'll test one tomorrow to see what the voltage shows. If it shows 12V, then the lack of voltage may be the reason the PCM isn't triggering the PCM Power Relay. If this one shows 1.5V is normal, then checking continuity between the PPR #1 slot and pin #40 on the PCM harness plug would be a good place to start.

 

I noticed that I didn't mention to check F28 with the ignition switch in the run position. If you didn't, then recheck it again with the ignition switched to run.

The rain finally let up enough to go out and check the voltage. F28 should have 12V. With the fuse removed the PPR won't energize, so the lack of voltage to the circuit is definitely part of your problem.

F28 is supplied from the ignition switch Start/Run circuit. It looks like F13, F14, F15, F16, F18, F19 and F27 are also supplied from the same circuit. Check those fuses with the ignition switch in the run position and see if they have 12V. If they do, then the problem may be in the CJB. If not, then the problem may be in the supply portion of the circuit.

Check F102 , it supplies power to the ignition switch circuit. You can swap it with another 20A fuse (F103 or F117) to see if makes a difference. If this isn't the problem, then the wires to and from the ignition switch, as well as the ignition switch itself, should be the next things to check.

The wires to and from the CJB and ignition switch are in a small black connector with 6 wires, located on the right side of the CJB at the bottom (according to the location diagram in the wiring manual). The power from F102 to the ignition switch is LG-VT (pin #4) and the return from the ignition switch for F28 (and the other mentioned fuses) is DB-LG (pin #3) from the connector.

 

Here we go...
Fuse F102 shows OK, and the box shows 12V at the contacts…
Fuses F13, F14, F15, F16, F18, F19, F27, F28 ALL showed 1.5-1.7 V, then I heard the aforementioned humming sound, then a CLICK, and all those [Fuses F13, F14, F15, F16, F18, F19, F27, F28] became alive with 12V…

I started tracking the humming sound and I found a relay under the dash that should not be there, so I contacted the previous owner… turns out (and I knew about it before buying the truck) this truck had an aftermarket K-9 Mundial/SSL/150 of some kind, and we both understood it had been eliminated COMPLETELY. Guess what: the control module had been eliminated as well as most of the cables and stuff, but they left wired a relay that used to belong to the anti-carjacking option of the K-9 security system…

PROBLEM SOLVED…

Oh boy… I feel like an idiot…

…and ashamed about asking all those questions and having fellow members taking their time and making an honest effort to help me the best they could with honest answers… and I was certain that the previous security system had been completely removed…

As a NEW YEAR approaches… a toast to all of you that offer a WEALTH of knowledge only knowing that the reward will be helping a fellow member with a solution to their problem…

Thanks to everyone and HAPPY 2020 to ALL…!!!!!!

 

Good to hear you got it figured out. You can finally start driving the thing.

No need to apologize or feel stupid. You did have a break/disconnection in a supply wire to or from the CJB, exactly what you were testing for. Luckily the relay engaged when it did so you could see voltage get restored back to all the fuses you were testing. Lucky again it was giving you an audible clue (the buzzing) to where the problem was located.

Thanks and a Happy New Year to you.