Ford B-Max Forum banner

1 - 6 of 6 Posts

·
Registered
Joined
·
8 Posts
Discussion Starter · #1 ·
Posted here in case it helps another owner.
The wife’s Bmax refused to start with all the symptoms of a flat battery. It was the original 2013 one so was past its best.
However... after a jump start it had the spanner light and transmission fault message which didn’t go away after a battery change.
The fix was to plug in my OBDC dongle and using car scanner app on my iPhone simply clear the fault codes.
Problem gone.
Once the battery discharges below a certain level the TCM and ECU stop talking. A fault code is logged and on ignition switch on the code is read, the message displayed and the transmission and engine go into limp mode. In this case absolutely pointless as there is no longer an issue.
Replacing the battery isn’t enough, resetting the fault codes is required so the car no longer knows it had a problem.
I bought the dongle from Amazon a while back and use the free version of the app just to read and reset fault codes. £10 To buy and 10 minutes to use has saved me the hassle of a 50 mile round trip to a dealer and the £75 they charge.
 

·
Registered
Joined
·
212 Posts
Thanks for the heads up on this issue.
Nice to know about for the future.
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #3 ·
And an unexpected benefit... the occasional auto clutch judder in second has disappeared. I can only guess that somehow clearing every fault code has caused the auto box to change some learned settings or start again. Both of us have noticed so it’s not driver specific. Whatever, it’s made an improvement so I’m not complaining.
 

·
Registered
Joined
·
19 Posts
I second having a OBD reader. I have a Toughbook (CF-19 Mk7 modded to high holy ****) loaded with ForScan, FoCCCus and a knock-off HS-CAN OBD2 cable so I can program most modern Fords.
 

·
Registered
Joined
·
3 Posts
Posted here in case it helps another owner.
The wife’s Bmax refused to start with all the symptoms of a flat battery. It was the original 2013 one so was past its best.
However... after a jump start it had the spanner light and transmission fault message which didn’t go away after a battery change.
The fix was to plug in my OBDC dongle and using car scanner app on my iPhone simply clear the fault codes.
Problem gone.
Once the battery discharges below a certain level the TCM and ECU stop talking. A fault code is logged and on ignition switch on the code is read, the message displayed and the transmission and engine go into limp mode. In this case absolutely pointless as there is no longer an issue.
Replacing the battery isn’t enough, resetting the fault codes is required so the car no longer knows it had a problem.
I bought the dongle from Amazon a while back and use the free version of the app just to read and reset fault codes. £10 To buy and 10 minutes to use has saved me the hassle of a 50 mile round trip to a dealer and the £75 they charge.
This is the same problem that I have now. Do you mind me asking which dongle you bought from
Amazon - they have so many.
Also is access to the app included with the product. Thanks in advance for your help.
 

·
Registered
Joined
·
1 Posts
Posted here in case it helps another owner.
The wife’s Bmax refused to start with all the symptoms of a flat battery. It was the original 2013 one so was past its best.
However... after a jump start it had the spanner light and transmission fault message which didn’t go away after a battery change.
The fix was to plug in my OBDC dongle and using car scanner app on my iPhone simply clear the fault codes.
Problem gone.
Once the battery discharges below a certain level the TCM and ECU stop talking. A fault code is logged and on ignition switch on the code is read, the message displayed and the transmission and engine go into limp mode. In this case absolutely pointless as there is no longer an issue.
Replacing the battery isn’t enough, resetting the fault codes is required so the car no longer knows it had a problem.
I bought the dongle from Amazon a while back and use the free version of the app just to read and reset fault codes. £10 To buy and 10 minutes to use has saved me the hassle of a 50 mile round trip to a dealer and the £75 they charge.
Thanks for the advice, and the explanation of the TCM not talking to the ECU. My battery had run flat after I forgot to disconnect a chill box when I parked the car. Got a jump start, but the transmission fault message came up. It would only change up at around 4000 revs, and the manual override didn't work. Got an OBD reader on Amazon, plugged it in, cleared the fault code in seconds. I now have working transmission again, and my son can use the reader on his MX5.
 
1 - 6 of 6 Posts
Top