Td5 starting issues, crank sensor

Hi, I'm Martin. I've got an 04 Discovery TD5 Landmark and it's an unreliable POS.
I'm wondering if anyone can help me with some advice today.

I've got a known issue with the crank sensor wiring. Pretty sure I pulled the cable by forgetting to unplug the sensor during a clutch change in summer.

Previously had a high speed crank and noisy crank issues.

Yesterday it started lumpy, died and hasn't started since. I cut the plug off today and wired in the replacement, although this has bullet connectors and a lot longer wire.

I'm wondering if I haven't cut off enough old cable, but struggling to pull the loom far enough to cut a good length.

I haven't got a nanocom to read the new issue, but 1000% it's crank sensor

Last thing, the earth sheath. Is there anything I can get to replace this, and how does it work exactly as its allegedly earthed.

Cheers guys

The signal current within the sensor wiring is tiny, and so it is susceptible to electromagnetic interference. To prevent this the cable contains a flexible shield layer similar in concept to old-style coaxial cable (but much thinner). This shielding earths into one of the terminals in the red ECU plug. If you don't do this the signal will be corrupted by things like the starter solenoid and the ECU will prevent start.
The cable can become corroded at the plug preventing it from working and the lack of spare cable in the loom coupled to the really poor access means that is is usually much easier to replace the cable entirely. You can buy shielded crank sensor cable, fit a new sensor coupling, route the cable to the ECU, fit the two wires and the twisted shielding into suitable terminals and fit it to the ECU.

Si Click said:

The signal current within the sensor wiring is tiny, and so it is susceptible to electromagnetic interference. To prevent this the cable contains a flexible shield layer similar in concept to old-style coaxial cable (but much thinner). This shielding earths into one of the terminals in the red ECU plug. If you don't do this the signal will be corrupted by things like the starter solenoid and the ECU will prevent start.
The cable can become corroded at the plug preventing it from working and the lack of spare cable in the loom coupled to the really poor access means that is is usually much easier to replace the cable entirely. You can buy shielded crank sensor cable, fit a new sensor coupling, route the cable to the ECU, fit the two wires and the twisted shielding into suitable terminals and fit it to the ECU.

Click to expand...

Makes sense, I'll look at a wiring diagram and see if I can make sense of it.

Would something like this be suitable to change the lot? Ideally bypassing the current wiring as it'll be a nightmare to get out the conduit, and wiring straight from the ecu to the plug as you said.

https://www.ebay.co.uk/itm/2-Core-S...p2349624.m46890.l6249&mkrid=710-127635-2958-0

Yes, use that kind of cable or better connect this guy https://www.ebay.co.uk/usr/landrover-connectors?_trksid=p2047675.l2559 cos he does the whole CPS wiring with new plug and pins for the ECU connector to be plug and play

sierrafery said:

Yes, use that kind of cable or better connect this guy https://www.ebay.co.uk/usr/landrover-connectors?_trksid=p2047675.l2559 cos he does the whole CPS wiring with new plug and pins for the ECU connector to be plug and play

Click to expand...

Ordered the wire and messaged the guy, hopefully he can help as it'll be much easier. In the meanwhile I need to see if I can get this pile of scrap running.

So,

On Thursday I made a makeshift cable using tinfoil, 0.75 twin core and electrical tape. I spliced the wiring at the ECU plug and she started.

Friday, and my screened cable was delivered. I soldered the "repair" plug and wiring on, soldered the screen onto the ECU ground and soldered then other two wires. Now she's refusing to start.

I can only assume I soldered the wires around the incorrect way, I've yet to try but I'm wondering if there is a correct and incorrect way. The repair plug and cable is quite long too, would it be a better idea to get the plug as close to the shield as possible?

The Yuasa battery is showing recharge in the window. So the battery is relatively dead. Charging as we speak, unfortunately from a 1.4 diesel Skoda

Lastly, the ebay seller didn't reply to me unfortunately. So here we are.


Thanks in advance

Got it lads.

After reading the wiring diagram, the wires were soldered in backwards.

Skoda eventually put enough power in her to get her started.


Cheers!

Result! Congratulations.
When I rewired the CPS on my son's TD5 D90 it also refused to start. After a cup of tea and some swearing, I took out the brand new CPS sensor and replaced it with the old one. Fired up first time and has been running properly ever since.