↓ Advertise on Defender2 ↓

Home > Td5 > Help diagnosing engine cutting out issue
Post Reply  Down to end
Page 1 of 2 12>
Print this entire topic · 
TD5Ad&Alf



Member Since: 06 Jan 2025
Location: Staffordshire
Posts: 14

England 2003 Defender 110 Td5 CSW Belize Green
Help diagnosing engine cutting out issue
My newly purchased TD5 Defender 2003 has recently started cutting out usually after around 5mins of driving, it wont restart (Turning over/cranking but not firing) until I lock it and unlock it again when it starts normally first time, runs for a further approx 5mins then cuts out again (same process repeated gets it going again)
I may be out but I suspect something to do with the immobiliser, mainly because it starts again fine when locked and unlocked with the fob, although I haven’t read about anyone experiencing the car cutting out due to this? Usually just not starting in the first place?

Since I have had it I have noticed the interior lights don’t work on the door switches, but do when I switch them on manually. It has the green AS10 unit behind the cluster and a fob, the fob only appears to unlock & lock the doors, the immobiliser light on the speedo lights up/flashes when the car is locked and goes out when unlocked with the fob. There is no indicator flashing or horn sounding when locking or unlocking with the fob.

Is this likely to be an issue with the AS10 unit? Or should I be looking elsewhere (Fuel pump relay etc) I’m not sure if its connected but the EML light comes on just as it cuts out, but this could be due to the engine dying as it goes out as normal when the car restarts.

Any ideas?
Post #1057306 13th Jan 2025 9:16pm
View user's profile Send private message View poster's gallery Reply with quote
landy andy



Member Since: 15 Feb 2009
Location: Ware, Herts
Posts: 5787

2006 Defender 110 Td5 USW Zermatt Silver
Have you tried running it with the fuel cap off, just in case the breather is blocked, and stopping the fuel leaving the tank?

Can you always hear the fuel pump run?

I would recommend you fit a new battery to your alarm remote. The indicators should flash on locking, and unlocking. Not doing this is a possible sign of low remote battery.

Your courtesy lights should have the switch in the middle position, they should light up when a door is opened, and when the doors are unlocked with fob, then go off after a time, or on locking with fob.
Post #1057341 14th Jan 2025 11:12am
View user's profile Send private message View poster's gallery Reply with quote
TD5Ad&Alf



Member Since: 06 Jan 2025
Location: Staffordshire
Posts: 14

England 2003 Defender 110 Td5 CSW Belize Green
Good suggestion about changing the fob battery I’ll try that and if no better I’ll try running it with the fuel cap off, good suggestion also to listen out for the fuel pump, I’m not sure it was running when I was trying to restart it.
The interior lights and indicators are definitely not acting as you describe maybe that’s linked to the fob battery though as you suggest.
The cutting out is very consistent and regular, which is what makes me think it’s being caused by something electronic and possibly the AS10, I’d expect it more randomly if it was a bad connection/earth issue?
Post #1057355 14th Jan 2025 2:44pm
View user's profile Send private message View poster's gallery Reply with quote
landy andy



Member Since: 15 Feb 2009
Location: Ware, Herts
Posts: 5787

2006 Defender 110 Td5 USW Zermatt Silver
I’d definitely start with fob batteries Thumbs Up Thumbs Up
Post #1057359 14th Jan 2025 3:33pm
View user's profile Send private message View poster's gallery Reply with quote
TD5Ad&Alf



Member Since: 06 Jan 2025
Location: Staffordshire
Posts: 14

England 2003 Defender 110 Td5 CSW Belize Green
Yep I’ll give that a go, wont see it till the end of the week as work gets in the way!!

Is it possible for the AS10 to cut the engine after its started then? In instances like the fob loosing connection due to low battery? Immobilisers I've come across in the past will prevent an engine from starting but not stop it once running, I guess it could be a Landroverism! Laughing
Post #1057389 14th Jan 2025 7:21pm
View user's profile Send private message View poster's gallery Reply with quote
landy andy



Member Since: 15 Feb 2009
Location: Ware, Herts
Posts: 5787

2006 Defender 110 Td5 USW Zermatt Silver
Yes, but when mine is having a “moment”, it starts then stops, after seconds. Not minutes. But that’s not to do with fob battery, What I do know is when the indicators stop working with tha alarm then that is an indication of low remote battery. I question if the battery is also there to power the chip/transponder for the immobiliser.
Post #1057391 14th Jan 2025 7:37pm
View user's profile Send private message View poster's gallery Reply with quote
TD5Ad&Alf



Member Since: 06 Jan 2025
Location: Staffordshire
Posts: 14

England 2003 Defender 110 Td5 CSW Belize Green
Certainly a good place to start, I’ll replace the battery and try it again.
Post #1057392 14th Jan 2025 7:57pm
View user's profile Send private message View poster's gallery Reply with quote
NickMc



Member Since: 01 Oct 2014
Location: Norn Iron
Posts: 1648

Northern Ireland 2006 Defender 90 Td5 HT Bonatti Grey
Likely water intrusion on the 10AS box or the blue header under the drivers seat (RHD). You can split the 10AS and inspect the board easy enough.
Post #1057407 14th Jan 2025 10:51pm
View user's profile Send private message View poster's gallery Reply with quote
MadTom



Member Since: 10 Sep 2013
Location: Olomouc
Posts: 636

Czech Republic 1999 Defender 130 Td5 HCPU Baltic Blue
Lock and unlock has connection with immobilizer, but you have also whitche off power of the engine ECU, and switche off engine. There is no communication betweet engine ECU and 10AS after engine start, just once during the immo off procedure during engine start.
Before dismantling engine and/or fuel parts, try anothe engine ECU. Any type, just needed pairing with 10AS (or removed immobilizer). Not to drive the car far away, but to run the engine long enough, to be sure, that the problem is not in broken engine ECU. I have seen some, with only partly damaged parts inside. "Drobek" = The Small One - Discovery 2, "Blufínek" = The Blue Thing - Defender 130, and for me at least Ford Mondeo Smile
Post #1057448 15th Jan 2025 2:07pm
View user's profile Send private message View poster's gallery Reply with quote
TD5Ad&Alf



Member Since: 06 Jan 2025
Location: Staffordshire
Posts: 14

England 2003 Defender 110 Td5 CSW Belize Green
I’ll check for water ingress on the AS10 thanks, what’s the blue header under the seat?

Also does anyone know if the AS10 can stop the engine at anytime (maybe by controlling the pump?) I’ve read lots of posts where it’s stopped the car from starting but not once it’s been running for a while?
Post #1057451 15th Jan 2025 2:56pm
View user's profile Send private message View poster's gallery Reply with quote
TD5Ad&Alf



Member Since: 06 Jan 2025
Location: Staffordshire
Posts: 14

England 2003 Defender 110 Td5 CSW Belize Green
MadTom wrote:
Lock and unlock has connection with immobilizer, but you have also whitche off power of the engine ECU, and switche off engine. There is no communication betweet engine ECU and 10AS after engine start, just once during the immo off procedure during engine start.
Before dismantling engine and/or fuel parts, try anothe engine ECU. Any type, just needed pairing with 10AS (or removed immobilizer). Not to drive the car far away, but to run the engine long enough, to be sure, that the problem is not in broken engine ECU. I have seen some, with only partly damaged parts inside.



Sorry only just read this reply, I’ll still check water ingress around the AS10 but I wouldn’t expect it to be able to stop the car once running either, there was a small amount of oil in the red plug when I bought it but I’ve since replaced the injector loom and seen none since, I feel a nancom purchase coming 🤣
Post #1057452 15th Jan 2025 3:01pm
View user's profile Send private message View poster's gallery Reply with quote
MadTom



Member Since: 10 Sep 2013
Location: Olomouc
Posts: 636

Czech Republic 1999 Defender 130 Td5 HCPU Baltic Blue
Oil in cables is not a real problem, compared to watter in cables. But as female connector pins in injector harness going old and older, they weaken - because of time and because of heat/cold cycles, and slowly loosing contact. Injectors are powered/commanded from ECU with 85V/25A impulses. Unlike to connector to lights, these will not burn, i case od bad contact, but ECU will sense it.
Just tighten these pins a bit.
A for the oil going out ot the head - replace 2 O-rings. And wait for all oil in cables slowly migrates out.
But this is a bit different problem.
10AS can stop starter from turning and ECU from controlling injectors during engine start, but not stop engine from running.
I have repaired quite a lot of engine ECUs and seen some with partly broken or fully broken components, but still working at least a bit. This is why I recommend test car with another TD5 engine ECU (any type/version is enough for basic test), because this is simple and fast, compared to dismantling "half of engine" to look for possible non existing problem. "Drobek" = The Small One - Discovery 2, "Blufínek" = The Blue Thing - Defender 130, and for me at least Ford Mondeo Smile
Post #1057509 16th Jan 2025 6:20am
View user's profile Send private message View poster's gallery Reply with quote
TD5Ad&Alf



Member Since: 06 Jan 2025
Location: Staffordshire
Posts: 14

England 2003 Defender 110 Td5 CSW Belize Green
Had chance to have a further look at it today, I’m now fairly confident it’s not connected to the Immobiliser. When it cuts out the fuel pumps kicks back in and runs as it should when trying to restart.
I now know the car only cuts out when the engine is revved reasonably hard it will tick over happily for ever,
When revving it the engine management light comes on and it stalls, If I lock it and open it via the fob it will restart first time yevery time. Could this be a faulty CPS?

The alarm/immobiliser is a separate issue, I’ve replaced the battery in the fob, I also discovered the 15amp fuse was missing for the alarm under the drivers seat, replaced that and now the car flashes the indicators when locking. I’ve noticed the brown relay behind the gearbox is corroded and the contacts are burnt, when the car is locked via the fob this relay clicks multiple times.

Also the interior light is dead (when switching to “on” or with the doors) and the immobiliser light doesn’t work at all currently, checked the fuses and there is power to the 10amp number 30 fuse in the box behind the gear lever. I’m not sure it’s connected but the radio is also currently dead (and it wasn’t before!) obviously some gremlins playing somewhere!!
Any ideas?
Post #1057766 18th Jan 2025 6:00pm
View user's profile Send private message View poster's gallery Reply with quote
MadTom



Member Since: 10 Sep 2013
Location: Olomouc
Posts: 636

Czech Republic 1999 Defender 130 Td5 HCPU Baltic Blue
Did you try to read faults from engine ECU? Or better look on live data whith running engine and during the cut out. MIL lamp is not normal, and definitelly noc connected to imobilizer.
Fuel pump.is powered through relay. Thir relay is controlled by engine ECU. Simple switch, and it should run all time, when engine is running. "Drobek" = The Small One - Discovery 2, "Blufínek" = The Blue Thing - Defender 130, and for me at least Ford Mondeo Smile
Post #1057780 18th Jan 2025 8:43pm
View user's profile Send private message View poster's gallery Reply with quote
TD5Ad&Alf



Member Since: 06 Jan 2025
Location: Staffordshire
Posts: 14

England 2003 Defender 110 Td5 CSW Belize Green
Think reading the codes is the next step yep, I’m thinking of buying Nanocom as it will be useful for diagnosing the issues with the alarm also, does anyone have one for sale? Or any ideas where best to buy one?
Useful help so far appreciated!!!
Post #1057784 18th Jan 2025 9:02pm
View user's profile Send private message View poster's gallery Reply with quote
Post Reply  Back to top
Page 1 of 2 12>
All times are GMT

Jump to  
Previous Topic | Next Topic >
Posting Rules
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum



Site Copyright © 2006-2025 Futuranet Ltd & Martin Lewis
DEFENDER2.NET RSS Feed - All Forums