On my 2007 F350 6L manual transmission and crank windows the cluster and radio dies, and by know I am almost sure the cause is somehow associated with high humidity. Almost every time it happens is either foggy or raining or is really high humidity in the air. My speedometer left lower light also died about a year ago from 0 to about 30-40mi/hr. Power comes back on after a while, and looks like recently it takes longer every time. Any potential explanations?

 

 

Ohhhh, that's depressing. I feel good using wrenches from 3/8" up; circuit board term freaks me out. Plus I'm sure those medics are not in my insurance policy network.

 

When it happened to me it was my Alternator putting out to much voltage.

 

Turn on the headlights when it happens and it will almost always come back quickly. Can't turn them to auto, it must be to the on position.

 

Alternator overcharging? How do you fix that? I assume it is a built-in regulator. So, if I reduce the RPM and turn lights on I could confirm that the alternator is at fault? Electronics in the instrument cluster or anywhere else for that matter should not get power directly from the alternator, or am I wrong? I always have power before I start the engine, and this confirms that problem is related to moving parts since instruments work on just battery.

 

 

I measure on the battery, both passenger and driver side. Batteries are 12.8V; when I start the engine (idling), drops down to 11.8V. I did this really fast (raining pretty good) and wonder how long glow plugs stay on after you start, if any. For gas engines I believe alternator should provide over 14V. What is the correct procedure to do this? And could low voltage cause my instrument power issue? As soon as the rain stop I'll clean battery terminals; lots of oxidation.

 

Maintaining the battery terminals is a must on this vehicle, and cause both high or low readings.

There's a lot of information on the forum about how this trucks systems work and how to maintain all of it, that would be a good start for you.

At starter engagement you can go under 11v, under 12v during glow plug operation for the first 90 seconds is no unusual for a motor equipped with a stock 110a alternator. After which it will climb to 14.2v or thereabouts. Voltage will drop with electrical demands and drops additionally once the underwood temperatures go up and the regulator reduces max volt output to 13.8 to no boil off the batteries. So after 90 seconds your voltage can be between 13.8 and 14.4 will nothing engaged depending on battery replenishment.

Batteries after running will carry a surface charge over 12.6v. Even overnight you can have 12.7v at rest, but 12.6v is considered 100% charged. All the readings I'm mentioning are at the battery terminals, not within the harness.

 

Give the people at Circuit Board Medics a call and they can help with the diagnosis.
They also support FTE as a sponsor. You can PM there user here >>> https://www.ford-trucks.com/forums/member.php?u=658450

The issue likely is the Accessory Delay Relay and that is controlled by the cluster. But you can try and replace the relay in the CJB.
I will attach the PDF for the fuses and relays.

 

Measured again, and let the engine run for about 2-3 minutes. 14.06 Volts. While waiting the instruments went all dead for a second, maybe when glowing plugs disconnected.
Thank you Yahiko. When @xcrsp440 mentioned them first, I thought Circuit Board Medics was just a reference to car electronics, not something real.

 

They have taken good care of lost of FTE members.

 

Quince,

Believe it or not, we are real! We see a lot of these clusters in the shop for repair. Over the years, we have seen a few things on these trucks cause similar symptoms whether its the cluster, alternator, or wiring. If this were my truck, I'd look into the following things and see where the troubleshooting leads me. If you have any questions, let me know and I'll see what I can do.

The most common issue is a failing cluster. This can cause the cluster to drop out intermittently which then causes the radio and power windows to fail. If this ends up being the case, you can send it to us to be repaired, or purchase a replacement through our exchange option.
https://circuitboardmedics.com/ford-...luster-repair/

The second possible issue is a failing alternator. As mentioned by a couple other guys, the voltage regulator in the alternator can start to fail, which will cause intermittent spikes in voltage. When the system voltage spikes above 16v, the cluster will drop out, and then come back on when the voltage drops back to normal. Generally this causes a pretty quick spike that will last any where from a few seconds to a couple of minutes at most. This can be tested by monitoring battery/system voltage through a scan tool or tuner. A DIY way to monitor system voltage with a multimeter is to find an old cellphone charger that you don't use that uses a cigarette lighter port, cut the cord to expose both wires, and hook a lead of the multimeter to each wire. Plug the charger into the cigarette lighter and monitor the voltage with the multimeter. Quickly glance over to check for a spike over 16v when you notice the cluster dropping out.

The third possible issue is a loose power or ground wire going to the cluster. If any of these powers or grounds are not constantly supplied to the cluster, then the cluster will not power up properly, or it will not power up at all. I have attached the wiring diagram for that cluster and marked the powers and grounds. Troubleshooting instructions are below:
- With a multimeter on DC Voltage setting:
To test a power pin, touch the black lead to a grounded metal part of the truck, and touch the red lead to the power pin being tested. Result: you should see around 12v on the meter.
To test a ground pin, touch the red lead to a 12v power source (one of the power pins already tested and confirmed), and touch the black lead to the ground pin. Result: you should see 12v on the meter.

*The key to this test is to test each wire while the cluster is acting up, so you may have to disassemble the harness plug in order to more easily access the wires while the cluster is still plugged in. I have attached pictures to help with disassembly.
Power Pins:
1. On the black plug, check the wires for pins 13 (Red w/Yellow stripe), 22 (Black w/Pink stripe), and 26 (Light Green w/Orange stripe) for 12 volts with the key in the ON position. If any of those wires do not have 12v with the key on, then that wire is most likely loose in the plug, or chaffed or broken along the harness.
2. On the blue plug, check the wires for pins 13 (Black w/Light Green stripe) and 19 (Black w/Light Green stripe) for 12 volts with the key in the ON position. If any of those wires do not have 12v with the key on, then that wire is most likely loose in the plug, or chaffed or broken along the harness.
Ground Pins:
3. Also check the grounds which are pin 10 (Black) on the black plug, and pin 15 (Pink w/Orange stripe) on the blue plug. These wires should have connection to ground at all times.

Hopefully this helps narrow down the problem!

 

Just logged on here to ask about this exact problem on my '06. Thanks for the help!

 

To Circuitboardmedics, got the pdf but I see no pictures on your post. However, testing while cluster is acting is basically impossible since it happens so randomly. After monitoring voltage, did not see any spikes. The voltage stays at 13.6-13.8 with cluster power on or off. I still believe that what ever the cause is, humidity is aggravating the issue and cluster power is stabilizing in low or no humidity. How much do you charge for a rebuilt cluster? The back light from 0 to 30 m/hr on the speedometer is also dead. My truck is a basic, manual transmission, crank windows, manual door lock... air is the only "luxury". 2007 F350 extended cab, 8ft box. I can attach a picture tomorrow if needed.