 | Home > Technical > Defender TD5 wont start |
 
|
|
|
| Paulpen Member Since: 01 Mar 2014 Location: Somerset Posts: 20  
|
Many thanks chap - gives me something else to try
 |
||
4th Mar 2014 8:19pm |
|
| Paulpen Member Since: 01 Mar 2014 Location: Somerset Posts: 20
|
Massive thanks to Ratty and Fanatic from landyzone for coming out to have a look and it seems the plot thickens !
Immobiliser system seems ok. ECU wont communicate with Nanocom etc but we are suspecting that due to it not powering up. They spotted that there are a few dry solder joints in the ecu on the back side of it so they could possibly be the issue ? There is a issue with an earth between the gearbox and the body as linking them with a jump lead imporves the voltage at the under seat fuse box dramatically. But problem still seems the same. Fuses, relays, supplys and earths all test ok and whilst fiddling with bits in the drivers seat pan the pump did run for half a second but we have been unable to recreate that It did seem that when you take the handbrake off the guage drops slightly though ?! Although we have voltage and earths with a multimeter at the ECU plugs they advised I restet them with some load so am getting hold of a test light thing and hunting a correct ecu pinout to work with to do that. So in summary we still have the following symptoms when the ignition is on : No fuel pump priming No engine light coming on Temperature gauge reading 3/4's Wont start even with fuel pressure applied manually We came to the conclusing thats its pretty much wiring or ecu so more wiring checks required |
||
|
8th Mar 2014 2:21pm |
|
| bga86 Member Since: 17 Jan 2014 Location: Here and there Posts: 205 
|
Did you try the earth overlay that I said as it causes exactly these symptoms?
|
||
|
8th Mar 2014 5:11pm |
|
| Paulpen Member Since: 01 Mar 2014 Location: Somerset Posts: 20
|
Not yet as had no internet access where the vehicle is.
Is it pin 85 of the large black relay ? |
||
|
8th Mar 2014 5:43pm |
|
| bga86 Member Since: 17 Jan 2014 Location: Here and there Posts: 205
|
Yes I think so, can't remember without looking at wiring diagrams but you should have continuity between pin 85 and the brown wire at inertia switch one the bulkhead under the bonnet
|
||
|
8th Mar 2014 5:50pm |
|
| dorsetsmith Member Since: 30 Oct 2011 Location: South West Posts: 4554 |
 Click image to enlarge |
||
|
8th Mar 2014 7:20pm |
|
| Rikjward Member Since: 09 Mar 2014 Location: Herts Posts: 1  
|
Sounds very similar to my breakdown this Friday.
Traced it back to lose connection on pin 33 (ignition) on ecu black plug. Noticed when no contact was made fuel pump did not work and temp gauge was at max. Caused intermittent misfire on journey home and eventually complete cut out. Wiggling the cable (white) around brought the temp back back to normal and fuel pump back into life. My own experience with the td5 not starting prior to this resulted in a replacement ecu. If you have fuel pressure , cps is working and vehicle is not immobilised it should start. Mine took persuasion with ezzi start before it jumped back into life with the new ecu. |
||
|
9th Mar 2014 2:04am |
|
| Paulpen Member Since: 01 Mar 2014 Location: Somerset Posts: 20
|
Another day another update !
ECU has good earths at the 4 wires on the black plug It also has good wires to the relays under the seat. What it does not have is 12v !. It should have it at pins 3, 22, 27 and 33. We only have it at 33 so spent the rest of the day following the brown with ornage trace wires aqround the whole car (dash, engine bay etc). Wherever we find the wire when its supplied with 12v the ecu powers up and we get a running engine ! Once the engine is running the temp gauge behaves normally it seems - until you use the sidelights, headlights, indicators and handbrake !. I think this means one of a few things - I have either a bad earth, a broken 12v supply or a 12v supply thats shorting to earth before it gets to the ECU ?! Input would be appreciated with those ideas as im not electrically minded ! |
||
|
9th Mar 2014 7:31pm |
|
| bga86 Member Since: 17 Jan 2014 Location: Here and there Posts: 205
|
So the wire between relay and inertia switch is ok? If it's not, it won't earth relay which will not switch to supply 12v to the Ecu. That relay sends power to the three wires that you don't have power too looking at the wiring diagram. It takes two minutes to bypass that wire even just to rule it out. Had exactly the same symptoms with my own td5 about 8 months ago!
|
||
|
9th Mar 2014 8:24pm |
|
| Paulpen Member Since: 01 Mar 2014 Location: Somerset Posts: 20
|
It seemed it with contunitity but not yet tried putting a supply down it.
From looking at those 3 supply wires to the ecu in diagrams it seems they are involved with the fuel pump relay, glow plug relay and main relay. Ill be getting on the case with all that tomorrow night  |
||
|
9th Mar 2014 8:51pm |
|
| bga86 Member Since: 17 Jan 2014 Location: Here and there Posts: 205
|
Don't put a supply down it it's an earth wire!!!! If you have 12v at the main relay on pin 30 (green yellow wire) then it just be earth issue as this relay feeds the 3 pins you don't have power to. Strip a small part of outer wire casing off brown wire at inertia switch and also at pin 85 of main relay, get a 6ft section of wire and twist it round both the inertia switch and relay ends of brown wire that you've stripped and turn ignition on, if you have fuel pump and temp guage is ok then you know there is a break in that wire somewhere
 |
||
|
9th Mar 2014 9:16pm |
|
| Paulpen Member Since: 01 Mar 2014 Location: Somerset Posts: 20
|
I mean down the supply to it from the fusebox if its not there
Main relay pin 30 looks to be brown and light green in RAVE ? So its basically join the inertia switch 12v supply to main relay pin 85 ? Main relay being the yellow under seat relay ? |
||
|
9th Mar 2014 9:31pm |
|
| bga86 Member Since: 17 Jan 2014 Location: Here and there Posts: 205
|
No inertia switch earth to main relay 85 (earth pin) both are a brown wire
|
||
|
9th Mar 2014 10:15pm |
|
| Paulpen Member Since: 01 Mar 2014 Location: Somerset Posts: 20
|
Ahhh ok chap
I can onlt fins half the main realy diagram and one side of the inertia switch wiring and its driving me crazy 
Brown inertia switch to main relay pin 87 (main relay being the yellow one under the seat) |
||
|
9th Mar 2014 10:33pm |
|
|
|
| All times are GMT |
< Previous Topic | Next Topic > |
Posting Rules
|
Site Copyright © 2006-2024 Futuranet Ltd & Martin Lewis
