Right turn signal indicator on dash flashes fast.

[seasprite]

You need this and a windows laptop with forscan software

https://www.amazon.com/OBDLink-EX-FORScan-OBD-Adapter/dp/B081VQVD3F?ref_=ast_sto_dp

Sponsored

 

[airline tech]

There are numerous posts about Forscan, you can download for free but to access, you pay a small license fee. Then you also need the OBD2 adaptor to connct from Laptop to the truck.

Another option - Autozone , Oreielys - Etc. offer a free check, it just depends on the scan tool they are using will pick up codes other than (P) Powertrain codes. Example (P0301)
Modern Day OBD2 Codes: Include (B) = Body , (C) = Chassis , (U) = Network / Communication

For your specific - current issue, it should show one of the following codes.
If you are comfortable doing it, there are wiring checks you can do, I have a feeling that since the front and mirror lights appear good, then the issue lies in the Rear, which is a LED assembly and the complete unit has to be replaced.
You can try reseating connectors to the lights, as it just may be a bad connection.
But if you have a code, you will have a specific location to check.
Another spot, is an inline connector that feeds the trailer lights connector, even though you do not have trailer lights plugged in, there is still power up to that connector.
I do not know exact location at the moment for it - but it is under the rear bumper area.

DTC	Description	Action
B123A:11	Left Front Turn Indicator: Circuit Short to Ground	GO to Pinpoint Test B
B123A:15	Left Front Turn Indicator: Circuit Short to Battery or Open	GO to Pinpoint Test B
B123B:11	Right Front Turn Indicator: Circuit Short to Ground	GO to Pinpoint Test B
B123B:15	Right Front Turn Indicator: Circuit Short to Battery or Open	GO to Pinpoint Test B
B1247:11	Left Rear Turn Indicator: Circuit Short To Ground	GO to Pinpoint Test B
B1247:15	Left Rear Turn Indicator: Circuit Short To Battery or Open	GO to Pinpoint Test B
B1248:11	Right Rear Turn Indicator: Circuit Short To Ground	GO to Pinpoint Test B
B1248:15	Right Rear Turn Indicator: Circuit Short To Battery or Open	GO to Pinpoint Test B
B1D35:11	Hazard Switch: Circuit Short to Ground	GO to Pinpoint Test C
U1000:00	Solid State Driver Protection Active -Driver Disabled: No Sub Type Information	GO to Pinpoint Test B
U3000:49	Control Module: Internal Electronic Failure	GO to Pinpoint Test B
For other BCM Diagnostic Trouble Codes (DTCs)	-	REFER to: Body Control Module (BCM) (419-10 Multifunction Electronic Modules, Diagnosis and Testing) .

 

[FiberTech]

You need this and a windows laptop with forscan software

https://www.amazon.com/OBDLink-EX-FORScan-OBD-Adapter/dp/B081VQVD3F?ref_=ast_sto_dp

Thank you for the info.

 

[KrazyTrane]

Unless built into the light module all turn signal bulbs are in incandescent type. Pretty sure factory does not use dielectric grease on any of these bulbs or connections. Depending on environmental conditions the oxidation of contact surfaces does mess with the connections. Some maintenance and some dielectric goes a long ways to keep this at bay for a very long time. As soon as a factory bulb does go in mine will replace with LED that has can bus resistance. Brighter and will last as long as I own it.

Feel free to skip my soap box rant the moral is check the trailer module if hyperflashing is not resolved by traditional methods.

Rant is below:

I had the dealer install the lightbar sold by ford parts that fits under the tailgate and reacts with brakes, reverse and turn signals. 2 weeks later (3 weeks after buying the brand new truck) my right turn signal slowly started to act funky. Sometimes blink faster, sometimes slower sometimes normal. After a few days, it was hyperflashing. I assumed it was the lightbar install so brought it back. Dealer claimed it was a bad lightbar. So I had to wait for them to make a warranty claim for the new lightbar - 7 weeks of hyperflashing later - they called me in to replace the lightbar. Frankly, I was frustrated that they did not just remove the old lightbar to stop the hyperflashing while we waited for the new lightbar but, considering this is the same dealer who kept my front and back ford logos (I had black ones installed) bc they claimed there was a “core charge” which required lots of arguing before they finally admitted they sent my original blue ones (with 150 miles on them) to their body shop for use in repairs - I did not have an argument in me. Then I get a call telling me that the new lightbar still hyperflashed and that the truck hyperflashed when they removed the lightbar altogether so they needed to research the issue. Too bad they did not check that 7 weeks ago bc they were told by ford that it’s the trailer module causing the Hyperflashing. Now we’re waiting for that part to come available. They say it’s either the trailer module or the ecm - good thing it’s still under warranty other than I have to keep dealing with the dealership.

Sorry for long post - thought I would try and help others avoid wasting time but didn’t realize I had that much yo

 

[Trigganometry]

Feel free to skip my soap box rant the moral is check the trailer module if hyperflashing is not resolved by traditional methods.

Rant is below:

I had the dealer install the lightbar sold by ford parts that fits under the tailgate and reacts with brakes, reverse and turn signals. 2 weeks later (3 weeks after buying the brand new truck) my right turn signal slowly started to act funky. Sometimes blink faster, sometimes slower sometimes normal. After a few days, it was hyperflashing. I assumed it was the lightbar install so brought it back. Dealer claimed it was a bad lightbar. So I had to wait for them to make a warranty claim for the new lightbar - 7 weeks of hyperflashing later - they called me in to replace the lightbar. Frankly, I was frustrated that they did not just remove the old lightbar to stop the hyperflashing while we waited for the new lightbar but, considering this is the same dealer who kept my front and back ford logos (I had black ones installed) bc they claimed there was a “core charge” which required lots of arguing before they finally admitted they sent my original blue ones (with 150 miles on them) to their body shop for use in repairs - I did not have an argument in me. Then I get a call telling me that the new lightbar still hyperflashed and that the truck hyperflashed when they removed the lightbar altogether so they needed to research the issue. Too bad they did not check that 7 weeks ago bc they were told by ford that it’s the trailer module causing the Hyperflashing. Now we’re waiting for that part to come available. They say it’s either the trailer module or the ecm - good thing it’s still under warranty other than I have to keep dealing with the dealership.

Sorry for long post - thought I would try and help others avoid wasting time but didn’t realize I had that much yo

It’s pretty well known on here that “splicing” anything into the factory harness will result in erratic behavior. It the additional resistance the BCM senses that there are issues that need to be addressed. Factory approved accessories or not! You need an isolator on each tap to keep this from happening. If it were me doing this a small bank of opto isolators on each tap would make it work fine

 

[Phantomfixer]

This happened to me also (21 Lariat).Everything looked fine except for instrument cluster hyper flash on one signal.It turned out to be a defective tail light.Dealer replaced it and it works fine.Tail light cost was $1100 but fortunately under warranty

 

[KrazyTrane]

It’s pretty well known on here that “splicing” anything into the factory harness will result in erratic behavior. It the additional resistance the BCM senses that there are issues that need to be addressed. Factory approved accessories or not! You need an isolator on each tap to keep this from happening. If it were me doing this a small bank of opto isolators on each tap would make it work fine

Thanks for your thoughts - I’ll be sure to add isolators on everything moving forward. In re to the hyperflashing, wouldn’t the problem also be solved by removing the splice altogether? I.e. when the lightbar is taken completely out of the equation, the Hyperflashing would stop due to all taps into factory harness being removed.

 

[airline tech]

Thanks for your thoughts - I’ll be sure to add isolators on everything moving forward. In re to the hyperflashing, wouldn’t the problem also be solved by removing the splice altogether? I.e. when the lightbar is taken completely out of the equation, the Hyperflashing would stop due to all taps into factory harness being removed.

It should have but I think was not done was clear the fault code out of the BCM.
If no code then there is still an issue with the wiring or taillight assy, you may also have a bad bulb/light on the side that is hyper flashing.
I am curious what code is being thrown.
This will help pinpoint.
Or the point of splice or tap off is the issue and not the light bar itself.
It tap off and teed into connectors- pushed or damaged pin will have the hyper flash symptom. (More Resistance) at the connector

 

[KrazyTrane]

It should have but I think was not done was clear the fault code out of the BCM.
If no code then there is still an issue with the wiring or taillight assy, you may also have a bad bulb/light on the side that is hyper flashing.
I am curious what code is being thrown.
This will help pinpoint.
Or the point of splice or tap off is the issue and not the light bar itself.
It tap off and teed into connectors- pushed or damaged pin will have the hyper flash symptom. (More Resistance) at the connector

No code that I’m aware of (dealer has vehicle - it’s a warranty item so I’m letting them spend time snd throw parts at it). They determine it was not the lightbar (got a new one and still hyper plus they took the lightbar completely out and it still hyper). Ford told them to replace trailer module - wasn’t it either. Ford you’d them to replace bcm - wasn’t it. Now the tech is going through all the wiring. Truck only has 1000 miles on it so likely not any of the corrosive stuff others mention (especially since it started 2 weeks after I bought the truck and only had 200 miles on it). It’s been at dealer 10 days - I’ll update when they figure it out

 

[airline tech]

It is very frustrating for me to see Ford just shot gunning parts, do a proper diagnostic and set precedence as a worthy dealer that knows what they are doing.
Ok. I can see the Light Bar, but the TRM and BCM and zero wiring checks they are clearly NOT following the service manuals and do not have a technician who knows how to use a meter.
I would start at the point of (Splice / Tap) if looks / checks good then move back to the tail-light assy.
My thinking is the Light-Bar possibly took out the Tail-Light Assy (Turn-Signal-circuit)
due to the fact that the Light-Bar was robbing power for the circuit - next voltage user (drop) in the circuit.
I would ensure the ground circuit is good and secure at the ground point as well.

That would be my first check's and move forward from there - (Headlamp and Mirror)
One off the wall, outside the box thing I would do, is cycle the Hazzard Switch, Does It still Hyper-Flash? and will it reset the circuit to proper operation?

For a Tech that knows what they are doing it should take no more than 1 to 3 hrs. of labor to diagnose properly and that time frame includes ripping dash apart (if needed)

Hopefully they will get it fixed for you, it should not be this much of a hassle.

 

[OFC Ranger]

It’s pretty well known on here that “splicing” anything into the factory harness will result in erratic behavior. It the additional resistance the BCM senses that there are issues that need to be addressed. Factory approved accessories or not! You need an isolator on each tap to keep this from happening. If it were me doing this a small bank of opto isolators on each tap would make it work fine

Is an isolator different than a diode blocker?

If so, how? I've never used an isolator in anything, but plenty of diode blockers.

 

[Trigganometry]

Is an isolator different than a diode blocker?

If so, how? I've never used an isolator in anything, but plenty of diode blockers.

Isolator is a low voltage internally led driven relay. So supply side and output side are totally isolated. Works much like a mechanical relay but low voltage (20 ma) to a normal relay coil that uses more juice and would most likely throw the factory sensing of faults into an error code or hyper flashing

 

[Spazzz96]

Feel free to skip my soap box rant the moral is check the trailer module if hyperflashing is not resolved by traditional methods.

Rant is below:

I had the dealer install the lightbar sold by ford parts that fits under the tailgate and reacts with brakes, reverse and turn signals. 2 weeks later (3 weeks after buying the brand new truck) my right turn signal slowly started to act funky. Sometimes blink faster, sometimes slower sometimes normal. After a few days, it was hyperflashing. I assumed it was the lightbar install so brought it back. Dealer claimed it was a bad lightbar. So I had to wait for them to make a warranty claim for the new lightbar - 7 weeks of hyperflashing later - they called me in to replace the lightbar. Frankly, I was frustrated that they did not just remove the old lightbar to stop the hyperflashing while we waited for the new lightbar but, considering this is the same dealer who kept my front and back ford logos (I had black ones installed) bc they claimed there was a “core charge” which required lots of arguing before they finally admitted they sent my original blue ones (with 150 miles on them) to their body shop for use in repairs - I did not have an argument in me. Then I get a call telling me that the new lightbar still hyperflashed and that the truck hyperflashed when they removed the lightbar altogether so they needed to research the issue. Too bad they did not check that 7 weeks ago bc they were told by ford that it’s the trailer module causing the Hyperflashing. Now we’re waiting for that part to come available. They say it’s either the trailer module or the ecm - good thing it’s still under warranty other than I have to keep dealing with the dealership.

Sorry for long post - thought I would try and help others avoid wasting time but didn’t realize I had that much yo

I also had the ford tailgate light bar installed with the hyperflash and cross traffic blind spot not working. They replaced the lightbar and which didnt fix the issues. I took the lightbar off completely and the issues remained. The dealer ended up replacing the trailer control module which didnt fix it then replaced the rear lights...which did fix it.

I wish i could use the lightbar...but im not going to mess with it anymore.

 

[KrazyTrane]

I also had the ford tailgate light bar installed with the hyperflash and cross traffic blind spot not working. They replaced the lightbar and which didnt fix the issues. I took the lightbar off completely and the issues remained. The dealer ended up replacing the trailer control module which didnt fix it then replaced the rear lights...which did fix it.

I wish i could use the lightbar...but im not going to mess with it anymore.

That’s exactly my sentiment - i like the lightbar a lot but the electronics on these trucks won’t allow for it to be installed. Scary how much damage they do bc replacing an entire rear light with the sensors in it is very expensive. Which is why i suggest everyone take it a step further and do not tap into the existing electrical for anything bc they’re way too sensitive (due to the amount and type of work they do not bc they’re not built well) for anything more than what’s programmed in. I run new lines for everything. The aux switches on the tremor are very helpful for that. Hopefully, ford wakes up, realizes that we like trucks bc we can modify them and let us adjust the computer for different loads on wires.

 

[Colo_Ranger]

I’m having this issue now too. It’s only the right side. No bulbs out. I disabled the fast blinking through Forscan but it’s still blinking fast. Here’s the kicker: it only blinks fast a couple times at the start of the day. After it “warms up” then it blinks normal. Only fast blinking inside, the actual lights are normal.

ideas on what to check? The only think I can think of is that I tried to tune my truck and it failed. When it failed, the truck wouldn’t start and I had to “restore” the tune to factory several times before it would work. This is when the issue started. I thought I had a bulb going out, so I replaced the bulbs. All bulbs are functioning and this happened with the OE bulbs and the new LED bulbs.

Sponsored