aubrey

Is there no-one on the Briskoda VCDS map local that can help you ? I'm in NE London for example and I would.

Why not just copy the coding off your current unit before you disconnect it. Then you can recode as was ? You'd have the current coding on any VCDS scan if you have one saved.

On my 2016 Yeti the original EFB Battery was failing after 4 years. The stop start was never kickimg in by 2020, so 4 years. Replaced it with a Varta AGM battery and that is still going strong 6 years later.

Are you reading an increasing voltage on the Octavia Battery, measured with a jump lead disconnected. Could the battery be bad, possibly a single cell, and as you say not taking any charge ? Are your jump leads thick high current ones or the thinner core variety ?

I agree no one has offered any evidence either way. However I still prefer to play safe and do the coding. No-one has ever said doing the coding is bad in any way.

Also Topdon Carpal looks interesting but I've never personally used that. Looks good value though.

OBD11 or Carista would be cheaper

No idea really. I changed mine to a Varta AGM. so I had to code that due to the change of battery type to AGM. I have VCDS. I'm sure any like for like would do. So EFB+ and 70AH. I don't want to get into brand arguments and does paying more give better value when comparing working life. I'm sure you can go with their recommendation. If not coding then ensuring EFB+ and 70AH is more important for you.

See what it says on https://www.tayna.co.uk/ You should code a new battery to the car. That basically means plugging a suitable OBD device onto the car to tell the BMS (battery monitoring system) the battery has been changed. But if you buy like for like or very similar, like your current is EFB+ and 70AH then it is not so important. So swap battery as you would on any old car, a few warnings lights you'll see on battery change will clear themselves after a short drive.

I've only ever put supermarket E10 in my 1.2 TSI Yeti. Never been an issue tbh. Sure it even says E10 inside the petrol flap.

The sesnors are around £130 and screw in like a spark plug. How can they be £400+ ? I've had S2 one fail on my Yeti, the post cat sensor, replaced it with an OEM one from TPS and no further issues for years now. Is the car showing Oxygen Sensor B1 S1 or B1 S2 as a fault code ? I hope it was an OEM one you replaced it with.

Had to change this on my 1.2 Yeti. Yes underneath but not too difficult to get to. I just drove one wheel up a driveway onto the edge of a high kerb. Could then crawl under and remove. They can be tight, so a good soak in penetrating oil helps and a hot exhaust can help too. I used a lamda sensor socket to remove it, which is a deep socket with a slot along the side to put the cable through. I replaced with the VW Part from TPS and fault code cleared. No problems for 4 years since

You should change the serial number even if the battery type and Ah match. Changing the serial number resets the BMS to a new battery. But you're right it will probably be fine to just swap if Ah and battery type match. I have always put the battery change date in as the serial number, just means you can always read it later to see when you installed the battery. Many others just change from 00000001 to 00000002 etc. At the end of the day it is just change the serial number that matters, not what you change it to. So your choice if you want to pop by just message me but if battery type and Ah match then it may not be so necessary. Your change from 68Ah to 70Ah I don't feel is that different and as you say they're both AGM.

Where about in Essex are you ? I live in Newbury Park, Ilford. If you pass by I could code your battery in for free. It only takes a few minutes. Your Bosch Battery looks the same as the Varta one I fitted to my Yeti in 2020. I also changed to AGM, so the big coding difference for me was EFB to AGM.

You'd lose your clock time and trip mileage. No problems with the radio, it identifies itself to the dash module automatically. You will have some fault lights on reconnection, but don't panic as a quick drive round the block with some lock to lock steering turns and they'd clear themselves.

Just code in the new battery to whatever you purchased. I changed my original Yeti battery to a Varta AGM from Tayna when I swapped that out in 2020. Your choice of battery purchase but just tell the BMS, i.e. code it, whatever you decided on. Ah, battery type and a serial number change.

An LED would test 0.5v on diode test. I'm sure you could track trace and continuity check back a driver IC. It is rare for leds to fail though. The leds look surface mount, so you'd have to remove that white surround to test and trace. Are there any faults present when scanned ? Just wondering if there was a reason to kill the led.

I would do the ABS Bleed Procedure. I have done that on ny Yeti and you only need access to both front brake bleed nipples. This resulted in a much firmer engine running brake pedal than before the ABS Bleed Procedure. So both front wheels on axel stands with wheels removed. It is an easy procedure but you need a few litres of brake fluid in a pressure bleeder. The rear wheels can be bleed normally after the ABS Bleed procedure is completed.

Isn't Autohold only for a few seconds. To allow your foot to move from the brake to the accelerator ? So my Yeti for example the car will just roll backwards after that few seconds.

You obviously never had air in the ABS unit then. I did once by running the master reservoir dry and only noticed when air splattered out the bleed nipple. I found with air in the ABS you can do a normal bleed and get a hard pedal, but immediately on engine start the pedal sinks right down. An ABS bleed was the only cure for that. You must of just had air in the far end. A pressure bleeder would of helped there too. I always use a pressure bleeder now, like in that photo earlier, they do make the task simple.

The ABS unit needs an ABS Bleed to get air out of it, if you pushed aur into the system. A pressure bleeder alone won't do it, neither will loosening the connectors on the ABS unit to bleed there too. I know that because I've tried. It was only a OBD initiated ABS Bleed procedure that did work on both my Roomster & Yeti. I don't know if with other models of ABS units it may not be required, I'm simply reporting what I found. It is not a difficult thing to do with VCDS. My Roomster needed all 4 wheels bleed nipples accessable, the Yeti only the front wheels.

Always when you change the battery you have to reset the windows. I think the procedure is all wimdows have to be shut. Then each window you wind down and hold button for a few seconds, then wind up and again hold buttin for a few seconds. That needs repeating on every window. As said it is a common windows reset thing on a battery swap.

I've used these before and they're good : https://westsidemotors.co.uk/

I have a Matika dtw300z impact, also a laser 7708 disc puller. Both tools have got me out of situations with no effort

Why would air in the lines cause the calipers to not release ? To not release means either the cakipers are binding or the brake pressure can't release in the system. If anything air in the system would help the caliper pressure release. You say opening a bleed valve releases the pressure so I agree with you in thinking the master cylinder is not letting the pressure release back into the reservoir. I assume nothing is preventing the brake pedal from fully retracting and providing a fully released pedal state to the master cylinder. In that fully released state the master cylinder should just let fluid return to the brake reservoir. Like when you use a wind back tool on the brake caliper to change pads. The fluid should rise in the brake reservoir as the calipers are wound back, the master cylinder letting the fluid flow backwards. From what you describe that would not be occurring.