↓ Advertise on Defender2 ↓

Home > Td5 > Crankshaft position sensor issues
Post Reply  Down to end
Page 1 of 1
Print this entire topic · 
Mr.Jimbo



Member Since: 20 Jun 2024
Location: Rugby UK
Posts: 17
United Kingdom 2003 Defender 110 Td5 CSW Java Black
Crankshaft position sensor issues
Hi all, got an intermittent (it’s happened twice now in about 7-8 months) where I’ll park the car up driving normally, but come back to it (first instance around an hour, today only 10-15 mins) and the car will fire very briefly, but then just crank without starting.

In both cases I’ve wriggled the CPS sensor wiring/connector and the car then works as normal. After the first time I then took the connector off and cleaned the sensor and wiring/pins and it’s been fine since.

My question though is: should the CPS losing connection/failing actually stop the engine, or is it only used for reference at startup? I understood the ECU needs the CPS signal to be valid at all times, however my car’s behaviour suggests otherwise (or I’ve just been bloody lucky I’ve been parked both times)

On a side note, it blew the filling station attendants mind when I was able to move the car on the starter in 1st gear without it running!

Appreciate any thoughts on this issue. I’m tempted to replace the sensor now or at the least get an oscilloscope to look at the output (will double check the wiring again)
Post #1072592 31st Jul 2025 9:29pm
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: 5986
2006 Defender 110 Td5 USW Zermatt Silver
You sure it’s not the immobiliser kicking in?

Your first sentence sounds like it.

How old battery in fob?
Post #1072593 31st Jul 2025 9:38pm
View user's profile Send private message View poster's gallery Reply with quote
blackwolf



Member Since: 03 Nov 2009
Location: South West England
Posts: 17905
United Kingdom 2007 Defender 110 Puma 2.4 DCPU Stornoway Grey
The crankshaft position sensor is needed for the engine to run. The camshaft position sensor is only needed for the engine to start.
Post #1072596 31st Jul 2025 10:49pm
View user's profile Send private message View poster's gallery Reply with quote
Mr.Jimbo



Member Since: 20 Jun 2024
Location: Rugby UK
Posts: 17
United Kingdom 2003 Defender 110 Td5 CSW Java Black
Fairly sure it’s not immobiliser - as I’ve had the same but get a red EML with a lightning bolt before which a quick lock/unlock sorts it (tried that several times but no joy) Occurrence 1 was a lock/unlock prior to issue, occurrence 2 today it remained unlocked as I was just filling up.

I did wonder if it might be something like cam sensor not achieving sync, but strange that it fires up right after I mess with the crankshaft sensor.

Edit I should say, on the two times it does it I have no dash lights out of the ordinary, just the oil pressure which goes out with a bit of cranking and the charge light. No indication at all from the car that it shouldn’t start. It’s also a 2003 15p 110
Post #1072598 31st Jul 2025 11:39pm
View user's profile Send private message View poster's gallery Post Reply
Post Reply  Back to top
Page 1 of 1
All times are GMT + 1 Hour

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