Disconnecting The Battery

bluenose1940 · February 24, 2012

I am shortly going to do a couple of jobs on my 220d and for one of them I need to disconnect the Battery. I intend to leave it disconnected for a reasonable time because I am going to give Matus' suggestion a go "Increase your mileage in a few steps" to see if I can improve my mpg returns.

The question that I have regarding the Battery is in respect of the radio. I have read in another thread that the radio stations get deleted so will have to be re-set but, I have looked through all of the paperwork that came with my car and I cannot find a code number for getting the radio going again. I have always had such a code number with all of my previous cars, do I not need one with my Lexus?

Is it only necessary to disconnect the negative lead to do the job and, is it ok to put it on charge (if I should need to) with only this lead disconnected?

Is there anything else that needs re-setting when I do the re-connect?

Many thanks for any help/guidance.

dave1 · February 24, 2012

I am shortly going to do a couple of jobs on my 220d and for one of them I need to disconnect the battery. I intend to leave it disconnected for a reasonable time because I am going to give Matus' suggestion a go "Increase your mileage in a few steps" to see if I can improve my mpg returns.

The question that I have regarding the battery is in respect of the radio. I have read in another thread that the radio stations get deleted so will have to be re-set but, I have looked through all of the paperwork that came with my car and I cannot find a code number for getting the radio going again. I have always had such a code number with all of my previous cars, do I not need one with my Lexus?

Is it only necessary to disconnect the negative lead to do the job and, is it ok to put it on charge (if I should need to) with only this lead disconnected?

Is there anything else that needs re-setting when I do the re-connect?

Many thanks for any help/guidance.

A quick phone call to your local dealer should answer all your questions. Personally I would not charge Battery whilst in car let alone with positive connected. If Battery is disconnected totally there should be no risk of any sparks/shorts which could cause serious damage......just not worth it in my humble opinion.

Hope you find an improvement afterwards.

dgman · February 25, 2012

you won't have to put any codes into the radio,it's just a matter of retuning the stations.

the electric window operation will need to be reset though.you must lower and raise each window by the switch at each one and not from the drivers seat and that's all there is to reset.

bluenose1940 · February 25, 2012

you won't have to put any codes into the radio,it's just a matter of retuning the stations.

the electric window operation will need to be reset though.you must lower and raise each window by the switch at each one and not from the drivers seat and that's all there is to reset.

Thank you dgman and David for your input, very helpful thanks. I have trickle charged batteries on previous cars and without disconnecting any of the leads on the advice of mechanic friends of my son but, I don't think that I would risk it with my Lexus! They aalways stressed that it must be 'trickle charge' only

dgman, as you have only commented on the windows needing resetting (apart from the radio stations) I would assume that the SatNav is not affected in any way, not the Bluetooth phone link.