Auto. starts engine in "Drive"

shadysadie · 2nd November 2017, 16:15

Discovered today that my KV6 auto. can be started with "D" selected. Fortunately I had plenty of clearance in front of the car so no damage apart from a clean pair of trousers! Further (careful) investigation proved that the engine will also start with "Reverse" selected so can one of you knowledgeable people please point me in the right direction to cure this potentially dangerous fault?

tantallon · 2nd November 2017, 16:39

Detent on start inhibitor switch stuck .Check operation of switch

David Lawrence · 2nd November 2017, 17:26

Quote:

Originally Posted by tantallon

Detent on start inhibitor switch stuck .Check operation of switch

Mine does this as well. Jules found it out while he was doing its air con.

If you manage to solve it, please report back how you did it.

It was reported to me that this is sometimes a symptom of the ECU having been replaced with one from a manual car at some point, but never had the chance to check it out yet.

Proud owner · 2nd November 2017, 18:09

Yes it does sound like the inhibitor switch is not doing what its meant to. Mine was deliberately disconnected by the garage that re-installed the rebuilt engine in my P5B which with the weight of that car would have catastrophic consequences, plus my next door neighbours had gone in his Ford Granada, which as he parked in front of his house one day he smashed into a bay window which caused major structural damage to that half front ground and first floors of his house.

I wouldn't have a clue how to fix it, but would recommend it is fixed as a matter of urgency.

Tracker · 2nd November 2017, 22:09

I have this problem too - been present since I bought the car and seller warned me about it. I have changed the auto inhibitor switch with what appeared to be a good used one but it made no difference which seems to indicate it's not the switch. Do any of the T4 guys have any suggestions (if T4 can show anything relevant)?

BigRuss · 3rd November 2017, 00:33

You may be able to check if the ECU has been changed if you unplug the ECU and remove it it should have a Sticker with the car VIN number on it.
If it doesn't match or the sticker is missing then it's likely to have been changed.

I've come across this a few times now usually on diesel autos but the same applies to the V6

Russ

David Lawrence · 3rd November 2017, 05:57

Quote:

Originally Posted by BigRuss

You may be able to check if the ECU has been changed if you unplug the ECU and remove it it should have a Sticker with the car VIN number on it.
If it doesn't match or the sticker is missing then it's likely to have been changed.

I've come across this a few times now usually on diesel autos but the same applies to the V6

Russ

Can it be reprogrammed by a T4 if it does turn out to be a changed one?

I might have a chance today to send all my plenum clips down the engine bay and take a look.

BigRuss · 3rd November 2017, 09:46

In you case David if it is a manual ECU that's been fitted the I'm afraid it may need a replacement ECU depending on the age of your car.
Early Auto cars use NNN100720 the manual uses NNN100692
Later cars both Auto and manual use NNN500340.

If it's had an ECU set from another car, to get the car back to as it should be, is quite involved there's two choices
First the car can be reconfigured to original the ECU will need to virginised and configured to the car, the Vin in the immobiliser edited to the original along with new transponders for the keys. The ZCS coding may need correcting if the original config has been corrupted also

Other way is to change the electronic identity of the car to the Vin of the ECU set, this would need the LSM and IPK virginising and then configuring to the car along with reconfiguring the ZCS coding. This can present problems though as if the ECU set has come from an MG and it's a 75 or vise-versa then it can can cause some issues and the car would have to be booked in as it's opposite version if you needed to put it on T4 if you need to diagnose problems in the future.

Personally I'd use method one as it's the best way to do things.

Putting an ECU set on may get you going but it can and does cause all sorts of problems.

T4 will not reconfigure or virginise ECU sets from another car or IPK's and LSM's it's incapable of doing that, we use various equipment and software to be able to do this.

Russ

marinabrian · 3rd November 2017, 14:43

Quote:

Originally Posted by shadysadie

Discovered today that my KV6 auto. can be started with "D" selected. Fortunately I had plenty of clearance in front of the car so no damage apart from a clean pair of trousers! Further (careful) investigation proved that the engine will also start with "Reverse" selected so can one of you knowledgeable people please point me in the right direction to cure this potentially dangerous fault?

Is this the car that your sent the water damaged ECM to me for repair David?

Not that I would have altered anything during the coding transfer, however the EWS holds the key to whether a car is an automatic or manual.

Fortunately with the V6 this can be corrected in the same way as for a diesel, using the method Russ describes

Brian

shadysadie · 3rd November 2017, 15:40

This is indeed the car which had ECU water ingress and was successfully brought back to life by your good self, Brian. As soon as I get time, I'll check if the VIN numbers match and report back.

2nd November 2017, 16:15	#1
shadysadie Loves to post BRG Connie Auto KV6, Dorchester red Jap. spec. Auto KV6 and 1967 Volvo 122S "Amazon" Join Date: May 2014 Location: Norwich Posts: 310 Thanks: 234 Thanked 90 Times in 60 Posts	Auto. starts engine in "Drive" Discovered today that my KV6 auto. can be started with "D" selected. Fortunately I had plenty of clearance in front of the car so no damage apart from a clean pair of trousers! Further (careful) investigation proved that the engine will also start with "Reverse" selected so can one of you knowledgeable people please point me in the right direction to cure this potentially dangerous fault?

2nd November 2017, 22:09	#5
Tracker Loves to post MG ZT Join Date: Sep 2015 Location: Dunmow Posts: 350 Thanks: 139 Thanked 83 Times in 72 Posts	V6 auto starting in "Drive" I have this problem too - been present since I bought the car and seller warned me about it. I have changed the auto inhibitor switch with what appeared to be a good used one but it made no difference which seems to indicate it's not the switch. Do any of the T4 guys have any suggestions (if T4 can show anything relevant)?

3rd November 2017, 00:33	#6
BigRuss Premium Trader 75 CDT Tourer,2.5 Launch Saloon, Omipro MG/Rover (T4) Join Date: Jul 2007 Location: Liversedge, West Yorkshire Posts: 5,405 Thanks: 1,105 Thanked 1,340 Times in 661 Posts	You may be able to check if the ECU has been changed if you unplug the ECU and remove it it should have a Sticker with the car VIN number on it. If it doesn't match or the sticker is missing then it's likely to have been changed. I've come across this a few times now usually on diesel autos but the same applies to the V6 Russ __________________ Replacement Key Service http://https://the75andztclub.co.uk/...d.php?t=244732 Full T4 Testbook diagnostics available. Diesel ECU repair and replacement. Options enabled or disabled as required. Diesel X-Power 135 and 160bhp, Rover 1.8T 150 to 160 MG 160 V6 to 177 upgrades available P.M. for details.

3rd November 2017, 09:46	#8
BigRuss Premium Trader 75 CDT Tourer,2.5 Launch Saloon, Omipro MG/Rover (T4) Join Date: Jul 2007 Location: Liversedge, West Yorkshire Posts: 5,405 Thanks: 1,105 Thanked 1,340 Times in 661 Posts	In you case David if it is a manual ECU that's been fitted the I'm afraid it may need a replacement ECU depending on the age of your car. Early Auto cars use NNN100720 the manual uses NNN100692 Later cars both Auto and manual use NNN500340. If it's had an ECU set from another car, to get the car back to as it should be, is quite involved there's two choices First the car can be reconfigured to original the ECU will need to virginised and configured to the car, the Vin in the immobiliser edited to the original along with new transponders for the keys. The ZCS coding may need correcting if the original config has been corrupted also Other way is to change the electronic identity of the car to the Vin of the ECU set, this would need the LSM and IPK virginising and then configuring to the car along with reconfiguring the ZCS coding. This can present problems though as if the ECU set has come from an MG and it's a 75 or vise-versa then it can can cause some issues and the car would have to be booked in as it's opposite version if you needed to put it on T4 if you need to diagnose problems in the future. Personally I'd use method one as it's the best way to do things. Putting an ECU set on may get you going but it can and does cause all sorts of problems. T4 will not reconfigure or virginise ECU sets from another car or IPK's and LSM's it's incapable of doing that, we use various equipment and software to be able to do this. Russ __________________ Replacement Key Service http://https://the75andztclub.co.uk/...d.php?t=244732 Full T4 Testbook diagnostics available. Diesel ECU repair and replacement. Options enabled or disabled as required. Diesel X-Power 135 and 160bhp, Rover 1.8T 150 to 160 MG 160 V6 to 177 upgrades available P.M. for details.

2nd November 2017, 16:39	#2
tantallon Gets stuck in ROVER 75 SALOON Join Date: Apr 2017 Location: Peterborough Posts: 597 Thanks: 386 Thanked 316 Times in 144 Posts	Detent on start inhibitor switch stuck .Check operation of switch

2nd November 2017, 18:09	#4
Proud owner Loves to post Rover 75 Saloon Join Date: Apr 2017 Location: Braintree Posts: 443 Thanks: 159 Thanked 126 Times in 100 Posts	Yes it does sound like the inhibitor switch is not doing what its meant to. Mine was deliberately disconnected by the garage that re-installed the rebuilt engine in my P5B which with the weight of that car would have catastrophic consequences, plus my next door neighbours had gone in his Ford Granada, which as he parked in front of his house one day he smashed into a bay window which caused major structural damage to that half front ground and first floors of his house. I wouldn't have a clue how to fix it, but would recommend it is fixed as a matter of urgency.

3rd November 2017, 15:40	#10
shadysadie Loves to post BRG Connie Auto KV6, Dorchester red Jap. spec. Auto KV6 and 1967 Volvo 122S "Amazon" Join Date: May 2014 Location: Norwich Posts: 310 Thanks: 234 Thanked 90 Times in 60 Posts	This is indeed the car which had ECU water ingress and was successfully brought back to life by your good self, Brian. As soon as I get time, I'll check if the VIN numbers match and report back.