Multiple failures post a flat battery

[Telf]

Hi all.

First post here.

My Golf (1.9 TDI) had a flat battery. That was replaced. It started but then had a power steering warning light illuminate.

Investigating that led to checking a few fuses, in the midst of checking everything the car now wont start at all. No fuses were found blown.

So it now has 3 faults:
1. No start- cranks but wont start.
2. Power steering light on red (or flashing yellow if you pull and reset the associated fuse).
3. My basic code reader refuses to link with the car- it did initially and showed no codes.

I've never owned a Golf before so don't know alot about them but have built a 205 GTI from a bare shell so I'm no stranger to car tinkering.

Does the Golf have some weird faults post a battery change, I'm confused as to whats happened tbh.

Thanks

[Crasher]

The PQ35 platform (Golf 5 etc) is fully CAN BUS based and reacts very badly to poor voltages. If the car cranks and fires then cuts immediately or just cranks and fails to start at all both indicate different problems so crank and no start at all and no CAN BUS comms says a power supply problem to the engine ECU. At the very least you are going to need a specific VAG diagnostic system, preferably VCDS.

[Telf]

Hi, thanks for the reply.

I spent the morning faffing with the car and discovered Id made a boo boo. Spotted as the Eng management light wasn't illuminated. Fuse 25 (engine fusebox) wasn't present. I must have pulled it out and not replaced it - so that cured the no start. i then ran the car to a mates who has a decent code reader and got him to read all the faults- cleared them and now the Power steering is operational again.

I find it very odd that the car effectively latched the steering fault and refused to let it go after a battery change. Still modern(ish) technology what can you do!

[Crasher]

Electric power steering, ANYTHING you do upsets it and normally a test drive with some stationary lock to lock shuts it up. You had better get used to it, this is the future...

[Telf]

i tried stationary lock to lock and it did nothing at all - the reader had nearly every module reporting faults, ridiculous really. Im lucky i have a 1989 pug that has none of the modern nonsense on it- it just works and costs nothing to fix. These faults remind me why I generally dont bother with modern cars. Thanks for you help, appreciate it.

[Crasher]

This is why I am sticking with my 2003 Octavia 1U VRS, it isn’t cool or sexy just like myself but is reliable, dependable and easy to repair, just unlike myself. The only issue I am now having is that some spare parts are not off the shelf. I was disgusted and appalled the other day to find my rear wiper arms pivot point had failed after only 21 years and 195k miles and then found it was obsolete and had to order one from Chezcihia.