breeves002
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Joined: Sun Sep 06, 2015 9:56 am
Location: St. Louis, MO

Battery Temp Sensor Intermittent/Erratic

Wed Feb 28, 2018 6:29 pm

I was looking through FORScan on the car for the first time in a while and noticed I had 4 codes.

3 were in the BECM:
P0AC9 - Hybrid Battery Temperature Sensor B Circuit Intermittent/Erratic
P0C8C - Hybrid Battery Temperature Sensor 1 Circuit Intermittent/Erratic
P0C91 - Hybrid Battery Temperature Sensor 2 Circuit Intermittent/Erratic

I also had P0C4A in the PCM which I have seen before for "Hybrid Battery Pack Coolant Pump Control Performance". The heater coolant pump was replaced last year under warranty when it failed. Same code was there then.

I'm not sure what would causes these. No Freeze Frame data with them. I thought about clearing and seeing if they came back but if there's some reason I need to take it in let me know. Its under the ESP extended warranty with $0 deductible so as long as there is something to repair its free for me to bring it in. Otherwise I'll clear the codes and see if they come back.

I also had a U0100 in the ABS module for lost communication with ECM/PCM but I don't think that is anything important.
2014 FFE Tuxedo Black - Leather - EV ST
2016 Mustang GT Premium - Performance Package - 401A - 2018 Digital Cluster

sefs
Posts: 236
Joined: Thu Nov 21, 2013 10:00 am
Location: Gibsonia, PA

Re: Battery Temp Sensor Intermittent/Erratic

Thu Mar 01, 2018 2:54 am

Breeves,

Did you have the recall work performed on the lower battery, getting the connector checked out for cracking and the snow shield installed?
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breeves002
Site Moderator
Posts: 105
Joined: Sun Sep 06, 2015 9:56 am
Location: St. Louis, MO

Re: Battery Temp Sensor Intermittent/Erratic

Thu Mar 01, 2018 5:07 pm

I did have the recall work done. Car is up to date on recall work. The connector was fine as far as I know.

I will check the coolant in the morning. Good tip.
2014 FFE Tuxedo Black - Leather - EV ST
2016 Mustang GT Premium - Performance Package - 401A - 2018 Digital Cluster

breeves002
Site Moderator
Posts: 105
Joined: Sun Sep 06, 2015 9:56 am
Location: St. Louis, MO

Re: Battery Temp Sensor Intermittent/Erratic

Fri Mar 02, 2018 10:08 am

Update: Coolant level was right on the low line today while cold. I don't think I'd consider that low coolant. I'm going to clear the codes and see if they come back.
2014 FFE Tuxedo Black - Leather - EV ST
2016 Mustang GT Premium - Performance Package - 401A - 2018 Digital Cluster

breeves002
Site Moderator
Posts: 105
Joined: Sun Sep 06, 2015 9:56 am
Location: St. Louis, MO

Re: Battery Temp Sensor Intermittent/Erratic

Sat Mar 03, 2018 10:16 pm

Another update. I didn't drive the car on Friday and went to drive it this evening and the 12v battery was dead... I jumped it and it seemed fine but that was weird to me. Wondering if it going bad has anything to do with this issue. My guess is no though. I'll get a new battery soon.

Its crazy how fast these cars eat batteries.
2014 FFE Tuxedo Black - Leather - EV ST
2016 Mustang GT Premium - Performance Package - 401A - 2018 Digital Cluster

davideos
Posts: 408
Joined: Mon Jan 21, 2013 8:58 pm
Location: So Cal

Re: Battery Temp Sensor Intermittent/Erratic

Mon Mar 05, 2018 7:44 pm

Could be the battery, who knows. The 12V issues has created some odd issues. Go ahead and replace and see how it goes.

breeves002
Site Moderator
Posts: 105
Joined: Sun Sep 06, 2015 9:56 am
Location: St. Louis, MO

Re: Battery Temp Sensor Intermittent/Erratic

Thu Mar 08, 2018 8:59 pm

Battery is fine. IDK what caused it to die. I know there's a TSB on randomly dying batteries that came out a few years ago. Updating the GWM or some other module is recommended. There's also a TSB on the P0C4A code saying air gets trapped in the cooling system or coolant level low (I checked).

I let the car sit 3 days since I had a dealer loaner while my Mustang was being fixed and the battery is still fine. Drove it around the block tonight. Will drive it to work tomorrow.
2014 FFE Tuxedo Black - Leather - EV ST
2016 Mustang GT Premium - Performance Package - 401A - 2018 Digital Cluster

lmlaster
Posts: 14
Joined: Mon Oct 26, 2015 5:21 am

Re: Battery Temp Sensor Intermittent/Erratic

Sat Jul 20, 2019 7:30 am

I read your post. My car is having crazy problems during 90+ heat. My dealer checked the 12V battery and said it was good. Any guesses? They've had my car for 3 weeks now and waiting on Ford Corporate to interpret what the codes mean

Here is my original post
viewtopic.php?t=4860

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