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OBDII port not working...?

TKep

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Greenwood
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2018 Fiesta SE
#1
I have a ScanGauge ][ that I have used in multiple vehicles. Actually I have 2 of them. Neither one seems to work in my 2018 Fiesta SE. Both work in 2 other vehicles that I have. Is the OBDII port fused? Maybe? I cannot find any reference to it in the owner's manual.
 

scotman

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#2
I have a ScanGauge ][ that I have used in multiple vehicles. Actually I have 2 of them. Neither one seems to work in my 2018 Fiesta SE. Both work in 2 other vehicles that I have. Is the OBDII port fused? Maybe? I cannot find any reference to it in the owner's manual.
Hello. That OBD port should be powered up at all times. If you have access to a generic scan tool you could verify if it has an issue, because the gst is vehicle powered.
If that doesn't light up you will need to have a technician repair that pinout.
 
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Grand Rapids
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2019 Ford Fiesta SE HB
#3
Found this, that OBDII port should get power from the Passenger compartment fuse box...
1610780290177.png
Hope this helps!
 
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Northern
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CA
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2015 Fiesta SE HB Magnetic
#5
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'17 ST
#6
What is the fear here? Thieves do what with the OBD? I guess I need to be enlightened. BTW...at the end of the thread you quote, all I could think is....in a frontal collision your right knee is going to be sheared off.
It's not an issue in the US. Small cars aren't in demand here. In other countries, Fiestas are more popular, and they get stolen.
 
OP
TKep

TKep

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Thread Starter #10
Found this, that OBDII port should get power from the Passenger compartment fuse box...
View attachment 4467
Hope this helps!
That may explain it - then again, maybe not. I just checked and I do not have a fuse in F5 at all. Now, here is the weird part. My ScanGauge II worked in the ODBII port before I installed a negative terminal battery disconnect. Afterward it did not work any longer. I have never removed the fuse in F5. I have an appointment with my Ford dealer in the morning - will report findings afterward.
 
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Grand Rapids
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MI
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2019 Ford Fiesta SE HB
#11
Ok, and also brace yourself for you may encounter a OBD-II Block device - this device helps reduce the chances of "cloning" - which a thieves can use to tell the immobilizer that "I don't have the key - but hey, It's me" syndrome that is an exploit of a keyless entry system.

IT may have been installed at the prior owners request and was not removed before a sale - or the Dealer you got it from, installed it to prevent drive offs of their lot.

Not a big problem, but again, it allows codes to transfer and diagnostics to occur - but there are other features that it won't let the new owner do until it's checked over and if needed - pulled (it covers a set of contacts) off a cover that allow for a more in-depth test jig USB/Port access to PCM/ECU and CAM communications I think they call it a J-2534 protocol and communications - it's for the diagnostics and flash programming of systems with OBD-II systems.
 
OP
TKep

TKep

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Thread Starter #12
OBDII port issue resolved. F5 was missing the fuse as I reported earlier. Dealership installed a new fuse, problem resolved. I was still confused however. I looked under the floor mats that I had installed about the same time as the terminal disconnect and the missing fuse was under the mat. It must have been loose and coincidently fell at just the right time.
 
Messages
137
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City
Grand Rapids
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MI
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2019 Ford Fiesta SE HB
#13
Well, no! Don't be confused! Finding that Fuse - that's a good thing, because it is a safe way to disable the Clone-ability that thieves will use to steal your vehicle.

Else they would have to supply that voltage to obtain that access - once their battery is below a set point, the diagnostic handshake fails and they lose the ability to say "I'm here, it's Me"

Why your OBD thing worked? Well, there is a timer on the OBD power wires that is enabled thru the CAN (I said CAM earlier - meant CAN) they send power thru their lines to communicate to the other systems - like their "wake up" handshaking when you open the door - so until the "battery drain protection feature kicks in" that power is possible thru their CAN communication system.

If your scanner has that ability to look at CAN (like SRS, ABS TPMS) then I can see why you had some success in using your scanner.
 


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