Posts: 409
Joined: Mon Jan 21, 2013 8:58 pm
Location: So Cal

Re: Stop Safely Now Warning

Thu Jun 13, 2019 4:07 pm

Here's some comments from my experience. The SSN issues doesn't necessarily mean it is a EV related (8yr 100k) problem. I had an SSN issue a year and a half ago where my battery was replaced. However, the week before that diagnosis was made, the dealer diagnosed a relay that was not covered under the warranty. Cost me $100 for the $25 part and $75 for the labor. However, I don't believe for a minute that this was the real issue...but I think that was the best diagnosis they were able to make. This was before I got my OBDII Bluetooth module and Forscan running. No hard feelings...I give the dealer the benefit of the doubt. However, it does reinforce something that I have come to know...there are likely 100s of possible issues that lead to the same symptom...SSN. This is why I purchased the Forscan setup; so I don't have to rely on the dealer to tell me what's wrong.

In this case, I'd try a different dealer. When I had my issues, they didn't charge me to diagnose. Their position was that they would do the diagnosis and then seek payment from me or from Ford depending on the outcome. Sure, you have to trust they do the right thing, but I've been doing pretty good by my dealer...even with the $100 I paid for what I thought was an incorrect diagnosis. But, I think my dealer is much better than the one who wants to be paid for the diagnosis. Could be they don't know how to effectively diagnose the car and want to be paid for their time in case they are not efficient. If possible, find a dealer others have used for EV troubles. I do agree that Forescan is a good first step; but it isn't always a slam dunk.

Here are my Forscan experiences.
1) After I had the battery swap, the car was getting charging faults. Took me 2 days to notice that the temp of the on-board charger was getting too hot...using Forscan. Oringinally I was monitoring the charging current and noticing that it was starting out with a high current but eventually throttling back...eventually down to 1 to 2 AMPs before stopping and issuing a charge fault. I also noticed a funny sound which turned out to be one of the cooling pumps running dry. Eventually I noticed the high temp of the charger using Forescan and then noticed the coolant was very low. Dealer forgot to put coolant back in after swapping the battery. The charge circuit is in the same coolant loop. No cost to me; dealer fixed.

2) After about 1 year after the battery swap, I got SSN again. Got it quite a few times. Using Forscan I could see a communication fault between the TCU and the battery. There was another issue logged, but I don't remember what it was. After taking it to the dealer, they double checked the TSBs and sent me on my way. I got an SSN 2 times on the way home but I was able to get it home. Called the dealer and dropped it off the next day. Got a call mid day that it was ready. They went from connector to connector looking for an issue and found that the main battery connector at the rear passengerside wheel was not fully seated....likely another issue from the battery swap a year earlier. Forscan wasn't too helpful to me at the time, but in retrospect it made sense. No cost to me.

3) I got a yellow wrench thrown. I had this issue off and on well after the 3 year 30k warranty with respect to the cruise control. Cruise control would work, but if I tried to press the "resume" after disengaging with the brake or "cancel", I'd get a yellow wrench. I read the codes with Forscan and it indicated an issue with the steering wheel module. After a wrench was thrown a subsequent time, I noticed that the cruise control wasn't working at all. Later, with no yellow wrench, I noticed that the cruise control wasn't working at all. The error code, when searched online, indicated some issue with other steering wheel controls. Long story short, I suspected that the switch contacts were likely not conducting very well due to lack of use. I ended up just working the switches a bit aggressively and the problem went away. No more yellow wrenches and the Forscan errors are no longer generated....and cruise control is working. There is a good chance it is a coincidence, but at least I do see correlation with Forscan and its ability to help diagnose.

Anyway, for this case, find another dealer :)

Posts: 52
Joined: Mon Oct 22, 2018 2:23 pm

Re: Stop Safely Now Warning

Tue Jul 09, 2019 1:04 pm

I'm resurrecting this thread to report another SSN on my 2012 FFE. DTC code is P0A0A. This issue has been going on for 2 months now. Dealer has already replaced the harness, the PCM. Car always shut down coming to a stop as I remember. It happens very random so I don't know. The good thing is that this car is still under the extended warranty. The bad thing is that I have taken it into the shop so many times that I rarely drive it now.

Posts: 52
Joined: Mon Oct 22, 2018 2:23 pm

Re: Stop Safely Now Warning

Fri Jul 19, 2019 8:47 am

Has anyone had this issue with their cars? I believe that the SSN for my car will come on if I hit the accelerating pedal and release it too many times in a short interval. I have a feeling that the voltage fluctuation causes the interlock circuit to lock up. Anyone got any idea? Thanks.

Posts: 117
Joined: Thu Feb 21, 2019 11:46 pm

Re: Stop Safely Now Warning

Fri Jul 19, 2019 10:55 pm

I just did a quick google search on P0A0A. So generically, when there is an HVIL failure, this code is set.
HVIL is High Voltage Interlock Loop.
I made a post a couple of weeks ago about a poorly connected high voltage connector in my 2017. In that, I talked about 2-stage high voltage connectors.
Well, for the more important high voltage connectors, the second stage has an additional set of contacts, that sense when the connector is connected or disconnected.
This separate set of wires that do not carry high voltage, but run along the with the high voltage cables, form a loop through out the vehicle. The Wiring diagram shows this best.
Anyway, whenever a high voltage connector is disconnected, the loop opens up. This open is sensed, and the high voltage system shuts down.
So imagine that you have a crummy connection for the HVIL. The car will think that a connector is becoming loose, and will shut down the high voltage as a safety precaution.
I will describe the HVIL loop as I see it in the wiring diagram.


The first loop "starts" in the PCM powertrain control module. Connector C175B pin 59
It then goes to the BJB battery junction box. Connector C1035C pin 5
It then goes to the GFM2 generic function module 2. Connector C1838A pin 9
It then loops through GFM2 connector C1838C out pin 3 and in pin 4
It then loops through GFM2 connector C1838D out pin 3 and in pin 4
It then loops through GFM2 connector C1838E out pin 3 and in pin 4
It then leaves the GFM2 connector C1838A pin 7
It then goes to the BJB connector C1035C pin 13
it then goes to the TCM transmission control module. Connect C1822A pin 13
It then loops through TCM connector C1822B out pin 4 and in pin 3
It then leaves the TCM connector C1822G pin 1
It then goes to the DCDC DC to DC converter control module. Connector C1457A pin 4, where it "ends".
The second loop "starts" in the DCDC connector C1457A pin 3.
It then goes to the TCM connector C1822G pin 2
It then loops through TCM connector C1822E out pin 1 and in pin 2
It then loops through TCM connector C1822C out pin 1 and in pin 2
It then leaves the TCM connector C1822A pin 14
And finally goes to the PCM connector C175B pin 55, where it "ends"

So by looking at this diagram, it appears that if there is a break in the HVIL, it will either be reported by the PCM or the DCDC.
It also appears that there are 12 connectors where as HVIL is sensed. This is for a 2017, so for a 2016 and earlier, it would be fewer connectors.
The connectors are:
C175B - 12v logic connector
C1035C- 12V logic connector
C1838A -
Last edited by Heima on Sun Mar 22, 2020 4:25 pm, edited 1 time in total.

Posts: 71
Joined: Fri Nov 02, 2018 2:14 pm
Location: Belarus, Minsk
Contact: Website

Re: Stop Safely Now Warning

Sat Jul 20, 2019 1:33 am

On my FFE, I soldered a HVIL control circuit. Near PCM)
I use translator. Sorry for the mistakes.

Posts: 52
Joined: Mon Oct 22, 2018 2:23 pm

Re: Stop Safely Now Warning

Mon Jul 22, 2019 9:42 am

So there are 12 different things that could go wrong and the same code will come up. What a design!

Posts: 117
Joined: Thu Feb 21, 2019 11:46 pm

Re: Stop Safely Now Warning

Tue Jul 23, 2019 8:17 pm

So there are 12 different things that could go wrong and the same code will come up. What a design!
Maybe, there might be slight differences in the codes, that would help identify where the problem is.
Nevertheless, it might be possible to do a continuity check of the loop at a few strategic points to determine where the open is.

Posts: 5
Joined: Thu Dec 18, 2014 8:02 pm

Re: Stop Safely Now Warning

Wed Aug 07, 2019 1:02 pm

Add me to the list of SSN sufferers. I have a 2014 FFE with 45,000 on it. My car has been at the dealership since 7/5/19 and they still do not know what is wrong with it. Here are some relevant details:
- The wiring harness was replaced before I took delivery of the car back in 2014.
- I had one SSN incident in the first couple of weeks that was solved by reseating all of the connections.
- Next SSN error happened in April 2019. It was a one off and I thought nothing of it.
- I did experience the issue where my level 1 charge cord fried my home electrical outlet. Got a replacement cord but no assistance for the electrical repair at home from ford :x
- On 7/3/19 my teenage daughter was driving the car and started getting SSN errors. My phone was lighting up with texts from the car so I was able to tell her to stay off freeways and be aware. It happened 8 times over the course of about 10 miles of surface street driving. I had the car towed to the dealer (nearest one is about 20 miles freeway driving away) on 7/5
- At some point in the past month they offered us a loaner since it was taking so long. I thought this was because it was covered under the extended warranty. Not so sure about that now.
- On 8/1 we went to pick up the car. At that time they had 15 hours of labor on the car, replaced the charging ring, some other connectors and reprogrammed "9 out of 15 modules" in the car. All should be good and they will work with Ford to reduce the cost of my bill (you BET they will! 15 hours of labor is exorbitant. Tells me they don't know how to diagnose the car).
- Drove away. Daughter driving again. Got 4 miles from dealership and were going about 70 MPH on freeway when SSN pops up again. This time it was VERY DANGEROUS.
- Pulled over, restarted the car and took surface streets back to the dealer where the car is today. They are still diagnosing it. The tech wants to put in a new battery but Ford has not approved that yet.

Meanwhile, I am driving a brand new Fusion Hybrid (had 6 miles when they loaned it to me). This car is not to shabby but I want my car back.

Posts: 77
Joined: Tue Nov 24, 2015 2:14 pm
Location: Vancouver

Re: Stop Safely Now Warning

Thu Aug 08, 2019 8:08 am

shniestEV wrote:
Thu Jun 06, 2019 12:38 pm

Needless to say... passed warranty... they want to charge me $900 for diagnosing my car all this time.... said the error code indicates wiring harness. Wiring harness cost is $1700 plus installation so total bill will be almost $3000.

I asked if they did any of the standard troubleshooting like inspect all the connections etc before ruling that the ENTIRE cable is bad. Considering the vehicle can work fine for a month with no issues.

Told them to give me my car back and I'm not paying anything. I don't even trust driving the car anymore. as who knows where, when and how often its going to pop up.

But thinking that my dashcam had issues getting power to run and charge its internal battery maybe i do have a 12v battery issue and could that be the cause of an SSN error? I'm thinking of not paying any money to get my car fixed as per the dealers diagnostics and just trying a new 12v battery. I have since removed the dash cam altogether in case it to also caused some kind of system fault in the wiring.
An update to my issue. Long story short... it definitely was not a HV wiring issue and so glad i didn't pay $3000 to fix it. I complained to the dealership and to Ford Canada about their misdiagnoses and told them its crazy that their diagnoses would have led either myself or ford down an expensive path when i simply asked them to test the 12 volt system. Replaced the battery and reconnected the dashcam and everything has been perfect. Dashcam is working correctly and no more SSN in the few months since picking up the car.

I believe the cause of my SSN was the 12v battery getting to low to the point it was causing faults in the accessory circuits when the vehicle attempted to put additional load on it. Replacing that was a lot cheaper than anything ford suggested (even though i asked ford to check and or change it).

Ford canada followed up a few weeks ago and I let them know my frustration and the craziness of the dealership invoice they are trying to slip me. I have not heard back from the dealership since i left my complaint and picked up my car.

Anyways... car has been working great since...and my dashcam is charging and working normally.
2016 Magnetic FFE - Canada

Posts: 52
Joined: Mon Oct 22, 2018 2:23 pm

Re: Stop Safely Now Warning

Fri Aug 09, 2019 5:25 pm

For my case, it wasn't because of the 12V battery that caused the SSN issue. I did replace the battery and it worked for a couple months. After that, and when the weather was hot I started getting SSN again. This time they replaced the PCM, harnesses. I got it back 2 weeks ago and it seems to work well now. I will update in the few weeks to see if SSN comes back.

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