"System Protection Intervention" Start/Stop system error

[BadHabit101]

Hi all, new to the forum

My 2018 Golf GTI PP (6MT) has had an issue for about the last year or so where the Start/Stop system will happily stop the engine when coming to a stop as expected but will not start the engine automatically any more. When trying to trigger an automatic start by e.g. pressing the clutch in, a message on the dash says to “Start engine manually”.

I know there are a bunch of factors that contribute to a successful start/stop cycle and trust me I’ve checked through every single one I could find mention of online. I’ve driven with the Start/Stop status screen up and when it’s failing to auto-start the engine it comes up with “System Protection Intervention” after a few seconds, with the dash saying to start the engine manually. The engine starts on turning the key.

Even though my battery but was less than 2.5 years old and voltages seemed normal, I bought a new battery today (Bosch S05 A08) and fitted it but unfortunately nothing has changed - I get the same error.

After the issue started, I used OBDeleven to deactivate Start/Stop which removes the annoyance but I hate that there’s an issue with my car I can’t fix! (I activated the Start/Stop system again before testing with the new battery.)

There’s no DTC codes stored for this problem and I’ve already recoded the new battery in Gateway - Adaptations.

Anyone have any idea what my next steps should be?

 

[SmoothCat565]

Did you turn on this stop start feature with OBD11? I didn’t even know these cars engines had stop start

 

[BigLips19]

How many miles? 2018-19s have a 6 year/72k warranty so you might still be covered at the dealer

 

[BadHabit101]

Did you turn on this stop start feature with OBD11? I didn’t even know these cars engines had stop start

Start/Stop came as a standard feature on the Mk7.5 GTI in the UK, not sure about other countries.

How many miles? 2018-19s have a 6 year/72k warranty so you might still be covered at the dealer

I wish! The warranty for a new VW in the UK is only 3 years. Starting to think I might have to pay the ridiculous diagnosis fee at the local VW dealer if I want this fixed (£138 / $175) The ‘System Protection Intervention’ error isn’t mentioned anywhere online at all.

 

[2018gti]

the first thought I have is that it could be something with your neutral position sensor? the car’s systems might be (mistakenly) thinking your shifter isn’t in neutral and as a result it wouldn’t be safe to start the engine. take this with a grain of salt as I don’t have this system on my GTI, however, I want to retrofit it so I’ve looked into all the stuff you need for start/stop on a manual.

only other idea would be to monitor the live data of the gateway module or ECU to see if there are any clues there.

 

[BadHabit101]

the first thought I have is that it could be something with your neutral position sensor? the car’s systems might be (mistakenly) thinking your shifter isn’t in neutral and as a result it wouldn’t be safe to start the engine. take this with a grain of salt as I don’t have this system on my GTI, however, I want to retrofit it so I’ve looked into all the stuff you need for start/stop on a manual.

only other idea would be to monitor the live data of the gateway module or ECU to see if there are any clues there.

Good thought but when I’ve got the Start/Stop status screen up and it’s trying to restart the engine, if I’ve got it in gear it’ll say to ‘disengage gear’ which goes away when I put it back in neutral. So it knows when it’s in gear or not. Same story for the clutch being up or down so I’ve ruled out those sensors at the moment.

 

[2018gti]

ok, that’s good, not the sensor then. yeah only other idea is to look through any “start/stop” entries in the live data, those can sometimes be more helpful than the warning that come up.

 

[The Fed]

OBD11 shows no faults? I'm only familiar with VCDS, but if the problem is something that's not monitored by the ECM, even VCDS won't show it.

This is the best I could find, maybe it will help:

The Start-Stop system relies on input from sensors monitoring the engine, battery voltage, vehicle speed, and other parameters. Faulty sensor data can trigger errors. Sensor diagnostics to perform include:

Throttle position sensor - Ensure it reaches high and low voltage values as the throttle opens and closes.
Engine coolant temperature sensor - Compare live readings vs gauge temp. Readings should correlate.
Vehicle speed sensor - Verify speed sensor reads zero when static and correlates to speedometer on a test drive.
Battery sensor - Check for stable voltage readings that align with battery tester values.
Sensor replacement may be required if output is erratic or out of spec after inspections. Consult a service manual for required values.

https://www.goodfellasautotn.com/bl...e#what-does-the-start-stop-error-message-mean