FK8 Battery Charging
- Thread starter Dshogg
- Start date
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- 56
I dont see why you cant charge it with it still being attached (still in the car).
I charged my battery over the last few months (not a Civic) with the battery still wired in with no issues (that I can tell).
Happy to be corrected though.
I charged my battery over the last few months (not a Civic) with the battery still wired in with no issues (that I can tell).
Happy to be corrected though.
The battery on the fk8 is a little weak and soon goes flat if the car is not used regularly.
Page 713 of the owners manual states that the battery should be disconnected before charging. However, if you do this, you will get the full Christmas tree warning light display on restarting the car on reconnection, and the ecu will spend the first few minutes of the next drive having to re-learn all the systems.
I couldn’t be bothered with that hassle on my 2018 fk8, so use a CTEK msx 5.0 battery maintainer without disconnecting. Been doing it regularly for 3 years now with no problems. Bear in mind that if you do charge without disconnecting the battery, that you do so at your own risk because of the requirement in the manual.
Worth noting that most dealers will connect a similar maintainer to your car whilst they work on it to avoid handing the cars back to customers with flat batterries.
If you do decide to charge without disconnecting, you would have to use a good quality battery maintainer such as the CTEK msx 5.0 though, not just any old charger.
Page 713 of the owners manual states that the battery should be disconnected before charging. However, if you do this, you will get the full Christmas tree warning light display on restarting the car on reconnection, and the ecu will spend the first few minutes of the next drive having to re-learn all the systems.
I couldn’t be bothered with that hassle on my 2018 fk8, so use a CTEK msx 5.0 battery maintainer without disconnecting. Been doing it regularly for 3 years now with no problems. Bear in mind that if you do charge without disconnecting the battery, that you do so at your own risk because of the requirement in the manual.
Worth noting that most dealers will connect a similar maintainer to your car whilst they work on it to avoid handing the cars back to customers with flat batterries.
If you do decide to charge without disconnecting, you would have to use a good quality battery maintainer such as the CTEK msx 5.0 though, not just any old charger.
Last edited:
- Messages
- 138
I've disconnected my battery to charge it after it was standing and not being used early lockdown. Only issue I had was the car re-syncing with the key for the immobilizer, to do this just hold the key close to the starter button.
Funny thing was, my dealer said not to disconnect the battery! And they didn't know how to re-sync either!
I learnt about it from having to call the AA tech team
Funny thing was, my dealer said not to disconnect the battery! And they didn't know how to re-sync either!
I learnt about it from having to call the AA tech team
- Messages
- 437
ooh didn't know that would work, I had to replace the battery in the keyfob yesterday and found it had lost association with the car. So followed a google procedure that involved getting in the car with both keys, and then within 5 seconds of pressing the ingition button (but not actually staring the car) you hit the lock button on the fob I had just replaced the battery in and it worked.
that said, the new fob might have just been close (less than 1 metre) to the ignition button when I turned it "on" so it could've been that too.
JMR
TRO Supporter
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- 2,300
Yes the CTEK MXS 5.0 is great for just leaving on the car without disconnecting the battery.
I've had one connected to my car for the last few years.
A decent quality one like the above would be best, some of the cheaper ones you run the risk of back-feed through the rectifier
(as a budget battery charger manufacturer once told me lol)
I've had one connected to my car for the last few years.
A decent quality one like the above would be best, some of the cheaper ones you run the risk of back-feed through the rectifier
(as a budget battery charger manufacturer once told me lol)If you use a smart charger there is no need to disconnect the battery terminals. I have charged my battery using a Sealey 6A 9 cycle 6/12v compact auto smart charger. Advice from Sealey was that there is no need to select battery types the system determines battery type automatically. This is why when a battery is flat some chargers will not work.
If you do disconnect the battery then after charging the immobiliser will need to be reset to start the car. This is done by (1) Holding foot hard on brake & accelerator flat down on floor then (2) Ignition to I & let all lights come on, then ignition to II & let all lights come on, then off & release brake pedal & accelerator. (3) Foot on clutch & start car.
To reset the Body Control Unit which controls the Stop Start then the following procedure must be carried out:
Here is the 12 Volt Battery Internal Resistance Reset.
At every engine startup, the PCM updates and records the internal resistance of a 12 volt battery When the average of past internal resistance (multiple memories) exceeds a threshold value, the PCM is judged the 12 volt battery deterioration.
The 12 volt battery cancel or the PCM reset does not clear the recorded internal resistance values of the 12 volt battery in the PCM.
1. HDS - Connect (not needed to remember computer settings)
2. 12 Volt Battery Internal Resistance - Reset
1. Make sure all electrical items (the A/C, the audio, the lights, etc.) are off.
2. Turn the vehicle to the OFF (LOCK) mode.
3. Turn the vehicle to the ACCESSORY mode.
4. Turn the vehicle to the ON mode.
5. Start the engine, and let it idle for 1 minute or more.
6. Turn the vehicle to the OFF (LOCK) mode.
7. Repeat steps 3 through 6 four times or more.
8. NOTE: The internal resistance of a 12 volt battery may not be updated if the engine starts up immediately from the OFF (LOCK) mode without going through the ACCESSORY mode and ON mode. Let all lights come on in ACCESSORY & ON modes.
9. Turn the vehicle to the ON mode.
10. Drive the vehicle and check auto stop start functions.
I have successfully used two times to get Stop Start, which I do not use, to function after battery voltage gets too low
If you do disconnect the battery then after charging the immobiliser will need to be reset to start the car. This is done by (1) Holding foot hard on brake & accelerator flat down on floor then (2) Ignition to I & let all lights come on, then ignition to II & let all lights come on, then off & release brake pedal & accelerator. (3) Foot on clutch & start car.
To reset the Body Control Unit which controls the Stop Start then the following procedure must be carried out:
Here is the 12 Volt Battery Internal Resistance Reset.
At every engine startup, the PCM updates and records the internal resistance of a 12 volt battery When the average of past internal resistance (multiple memories) exceeds a threshold value, the PCM is judged the 12 volt battery deterioration.
The 12 volt battery cancel or the PCM reset does not clear the recorded internal resistance values of the 12 volt battery in the PCM.
1. HDS - Connect (not needed to remember computer settings)
2. 12 Volt Battery Internal Resistance - Reset
1. Make sure all electrical items (the A/C, the audio, the lights, etc.) are off.
2. Turn the vehicle to the OFF (LOCK) mode.
3. Turn the vehicle to the ACCESSORY mode.
4. Turn the vehicle to the ON mode.
5. Start the engine, and let it idle for 1 minute or more.
6. Turn the vehicle to the OFF (LOCK) mode.
7. Repeat steps 3 through 6 four times or more.
8. NOTE: The internal resistance of a 12 volt battery may not be updated if the engine starts up immediately from the OFF (LOCK) mode without going through the ACCESSORY mode and ON mode. Let all lights come on in ACCESSORY & ON modes.
9. Turn the vehicle to the ON mode.
10. Drive the vehicle and check auto stop start functions.
I have successfully used two times to get Stop Start, which I do not use, to function after battery voltage gets too low