P01598 Error Code and Random High Idle - SOLVED

[Quiksilver_TR]

Here are my P01598 woes, its long winded but it may just help someone out that is suffering the same thing.

 

Car: 2010 Skoda Octavia VRS CR TDi 

 

I have had 12months of hassle with the P10598 error code (Drive Battery Closed) and changed, chased and investigated loads of things.

Ill write it like a diary to make things clearer.

 

 

October 2017

Car began to get sluggish to start, checked battery and it was only a small CCA 072 (550Ah) battery which had probably been on the car since new.

 

So I ordered up a new battery, 096 (CCA 770Ah) and got that fitted.

The same weekend I also fitted some LED headlight bulbs with error cancellers.

 

All seemed fine.

 

 

December 2017

Installed Pure Highway digital radio into the car. Hardwired into a heated seat fuse (my car doesn’t have heated seats so thought this was safe to use.

 

All seemed fine.

 

 

January 2018

Randomly…..the car starts idling high when sat at traffic lights. This isn’t a DPF issue, I can be 100% sure it isn’t.

Odd, but ill live with it.

Battery checked and all ok.

Alternator checked and all ok.

P01598 error code now present – reset and was fine for a week or so, then the revving returned.

So did the code, didn’t reset the code, lived with it.

 

March 2018

Its still doing the random idling, but now I’ve noticed that the power steering is feeling heavy when in use, but again this is random. Sometimes it will be fine, others it will be really heavy.

Electric power steering is high power consumption so I thought maybe the new battery is dead or the alternator is dying which is why the old battery was getting sluggish.

Battery checked and all ok.

Alternator checked and all ok.

P01598 error code present – reset and resetting on a weekly basis. Seemed fine for a handful of days and then the revving would return along with the error code.

It only did the revving/lack of power steering when the code was active and present in the BCM/Electronics control module.

 

Removed LED headlight bulbs and DAB thinking that they were the cause.

No improvement.

 

 

 

May 2018

Its still doing the random idling, and now the power steering switching off mid bend is just dangerous.

Battery checked and all ok.

Alternator checked and all ok.

P01598 error code present – reset and resetting every other day.

It only did the revving/lack of power steering when the code was active and present in the BCM/Electronics control module.

 

I spent the best part of 5hours removing earth wires, checking resistance, cleaning connections, refitting and checking continuity on as many earth wires as I could find.

Still no improvement.

 

 

I took the car to a garage and they ran a load of diagnostics and then showed me through the diagnostics and we decided that the alternator was most likely the cause as the terminal 30 voltage was all over the place. The expectation is that its steady 13.7-14.4v ish, instead mine was dropping to 10v and then spiking to 20v when the steering was turned.

 

I sourced a New Bosch 140A alternator which they fitted for me, reset codes and took my money.

 

All was great for 2weeks, when the revving returned again.

 

Live with it for a while as I didn’t know what to do.

In this time I trawled the internet to see what others had done, and I got nowhere.

 

 

July 2018

I re-fitted the old 072 battery to see if the “new” battery had been damaged by the spiking voltage.

Was fine for 2weeks, until the first cold’ish morning when I needed to use the rear demister and then the revving returned.

 

Thought maybe the demister was the cause, so reset the code didn’t use that for a while. Again it was ok for 2weeks and then returned on its own and was just as bad as before.

 

So not the battery.

 

Fitted the “new” 096 battery back in and again it was fine for a week and then it was back with a vengeance. Steering off more than on, revving more and more often.

Battery checked and all ok.

Alternator checked and all ok.

P01598 error code present – reset and resetting every day.

 

 

August 2018

Still doing it so as a last ditch attempt to prove the battery I bought another new 096 battery, this time a slightly less CCA 650Ah to see if the previous “new” battery was just too big for the car to handle.

I also investigated further to see of the battery needed to be coded and it didn’t.

Battery checked and all ok.

Alternator checked and all ok.

P01598 error code present – reset and resetting every day.

 

 

September – October 2018

I am really bored of the issue now, but its not in my nature to give up.

So I have been checking voltages religiously to see if there is a drain or issue.

 

No drain found.

 

I did discover this-

No code active/present:

Charging voltage 14.4-14.7v with nothing on. With all electrical items on it was running at 13.9-14v

 

Code active/present:

Charging voltage 13.5-13.7v with nothing on. With all electrical items on it was running at 13-13.5v

 

This to me was odd. The whole revving thing should be to assist the car in high load situations to charge the battery. So just why was it not letting more then 13.7v through when the code was present.

 

 

November 2018

I found this thread whilst I was searching for information on voltage control module information,

http://forums.tdiclub.com/showthread.php?t=386694&page=2

 

This was a line of enquiry that I hadn’t looked at before which is why I hadn’t found this thread previously.

Voltage control modules are only in cars with start stop, which mine doesn’t have, but I thought maybe there was something else in there that was causing the issue, hence the search.

 

I also noticed that the headlights pulsed (standard halogen bulbs) when the car was idling.

 

So, I set about running a new earth cable between the block and the battery.

Before doing this is did a load of checks again on voltage, continuity and resistance and all was ok.

Reset the codes (none present at this time, but reset all ECUs error memories anyway.

 

 

December 2018

So far, its been great. Touch wood and lots of it.

I will update this if the issue returns or if it stays "fixed"

 

 

Which earth wire is deficient I don’t actually know.

Maybe that should be my next task, is actually find the bad earth and fix it that way instead.....for now I would just like to enjoy it whilst its trouble free.

 

 

 

Some thoughts....

Why didn’t I do this sooner I here you ask…….well following the various checks of earths I thought it was fine.

Also when I have previously seen bad earths they are teamed up with starting issues or flat battery issues, which wasn’t the case. Must be a case that older cars without voltage correction capabilities suffer with start and drain issues, rather than being overly complex like the modern stuff and throwing a load of hassle into the mix.

 

I also think its very odd that when the car thinks it has a battery issue instead of raising the voltage capabilities it actually limits it to a less than optimal range but carries on and raises the revs anyway.

 

 

Hope this helps someone else.

Of course all investigations, part fitting, electrical work, diagnosis etc are done are your own risk and I (nor Briskoda) take no responsibility in any outcome.

[Quiksilver_TR]

02/01/2019

Another 4 weeks have past since I posted this and it’s still working 100%.

 

The car had been sat for the best part of 2 weeks over Christmas and had only been used twice for 2 very short journeys......and still no issue with it.

 

I have now also plugged back the extras, such as the DAB which have had no adverse effect, and on the 2 short journeys over Christmas and today’s work commute I’ve had all the lights on, demisters and blowers on flat out.

 

 

Jobs a good-un.

 

When the weather warms up a bit I will try and dig around for which earth is at fault.

[Skodanightmare]

Hello bud hope your still there, I got this exact same issue so what did you exactly do to solve the issue. Did you changed the negative earth terminal or I don’t understand what you did hope you reply many thanks

[Partridge1705]

Hi bud, thankyou for all of your info! First I've seen out of so many with an answer and it's solved the issue (temporarily), giving me chance to find the bad earth in my own time as you say. Thanks again!

[Quiksilver_TR]

On 20/03/2021 at 18:59, Skodanightmare said:

Hello bud hope your still there, I got this exact same issue so what did you exactly do to solve the issue. Did you changed the negative earth terminal or I don’t understand what you did hope you reply many thanks

Sorry, I don’t login very often.

i added a wire/earth from the alternator bracket directly to the battery.

 

 

On 28/11/2023 at 07:51, Partridge1705 said:

Hi bud, thankyou for all of your info! First I've seen out of so many with an answer and it's solved the issue (temporarily), giving me chance to find the bad earth in my own time as you say. Thanks again!

Cheers.

It was a temporary fix that is still installed and working 100%. Haven’t bothered hunting it down any further as I’ve been distracted with other projects.