Happy New Year! 🥂 I have just replaced the battery located in rear of car, in my 2003 V70 series 2 & now I have several warning lights (engine, brake fail,traction etc...)have tried disconnection & reconnection again but no success, engine starts & runs ok, but warning lights stay on. Any advice on resetting this manually would be appreciated, also correct procedure for replacing battery

Cheers

 

Start by checking fuses and then measure the voltage of your battery - both at the battery in the rear and the jumper terminals under the hood. Not sure if its possible to reverse the polarity on the install due to the position of the terminals but worth a look. Generally the process to replace the battery is pretty straight forward. When the key is off and out of the car, all accessories should be off. Given you need access to the rear (all my cars have front side batteries...) I'd probably wait for the interior light timer to go off. Now remove the battery tie down bracket or clamp. Remove the negative terminal first, then push out of the way (to avoid an accidental touch to the post), then the positive terminal. With both connections removed and with the tie down out of the way you can lift the battery out. Now clean the connectors with a wire bush and check for any bubbles in the cable's insulation, clean any connector components (like those metal brackets). Compare your new and old batteries and the positive and negative cables to orient the battery and drop in place. Confirm the battery terminals agree with the cable's polarity and now reinstall the tie down. Now connect the positive terminal first and securely press down the connector and tighten, then finally connect and tighten the negative.

At this point you are ready to start the car - so go to position 2 to see if the dash lights up. If so, give it a test start. If the warning lights remain you probably need to get a code reader to clear as its possible a low voltage or a spike set some false positive CEL codes.

 

Thank you, for the response. All cables & voltages have been checked & are good, car starts,runs & drives but warning lights stay on, just hoping that there is a way of clearing warning lights as I would have to drive 150 kilometres to find a dealer to clear codes.
Steve

 

1) Did you install a KNOWN NEW battery? Any chance of the terminals being shorted while this battery was lying about?
An old battery can read "12 volts" whilst unloaded but can drop to 10 or 9 when you turn the key.
This is frequently enough to kick the engine over but not enough to power all the systems adequately.

I've only seen H6 and H8 batteries as approved sizes. There are 2 threaded holes for the battery hold down back there.
Check to see that someone didn't shoehorn an old Group 48 into your car.
Steer clear of AGM batteries as the charging system isn't ideal for those. FLA (Flooded Lead Acid) only.

2) I've read many times that after removal of the battery AND a discharge period of, say, 20 minutes, one should touch the 2 battery clamps together. What exactly this does is something I don't know for certain but it cannot possibly hurt anything and I've been doing it for years on all vehicles.
My guess is that it discharges capacitors found on the many circuit boards.

3) Many times people have posted that the key should be inserted into the ignition and turned to position 2 before the battery is installed. The benefit claimed involves a "dampening" of sudden restoration of voltage. Unintended detonation of the airbags is the feared beast.

Just to confuse things: When I purchased my 2007 V70 at a Volvo dealership 3 years ago it's battery died. The articulate mechanic who was installing a new Volvo battery said he had never heard of the "key to position 2" step. However, many people on other boards claim this step is necessary.

4) Do you have access to any code reader at all?

 

I have spent a lot of time disconnecting/reconnecting the battery, trying all the recommended/suggested procedures but still no luck, the same warning lights (brake fail, traction control),still wont clear.
I managed to get a mechanic to try & clear the codes but still no success, he suggested I take it to a Volvo dealer (300k's round trip)!
Steve

 

The ABS controller drops off the bottom of the ABS unit. You need an external torx socket to remove it.
That'll be an E4 or E5 torx.
There are circuits in there which feature solder joints which fail. This part failing throws these codes.
You can drive without the ABS controller; i
You just won't have ABS brakes.

 

Woohoo!! I have had a win with clearing the warning lights!
Disconnected battery
Removed fuses related to warning lights that were showing previously. (ARS,Brake failure,traction control)
Reconnected battery with key in position 2
Turned key off, then back to position 2, then started engine, run for 30 second's.
Switch off (battery still connected)
Re insert removed fuse's
Start engine again
All warning lights cleared...Wow!
Not sure why this worked, simply used the principle of "create the problem, then fix it"
If any one could explain how/why this worked, I would be interested too know.
Thanks
Aussie

 

You "powered-down" some memory gizmo.
TRANSLATION: I don't know but I'm surely noting this procedure.
thanks for posting what you did.