Back to my non starting P38 2.5 DSE... the saga continues!

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jimmacD

jimmacD

Well-Known Member
Posts
378
Location
Lincolnshire
Does anyone have a wiring diagram for ignition, becm and ecu comms routes? Been busy with life.... fecking L322 threw a suprise spanner in the works with what I suspect is a failed timing chain guide.. totally out of the blue, started her up for School run and a bag of spanners rattles from drivers side front, ah bugger! She will have to sit until I have the pennies to repair, bit miffed as I had just serviced her and she was running great! Back to the P38, I have two weeks at home so have set a side the time to sort the old girl. I still feel as though the non start is due to Rodent/broken wire/poor earth somewhere but struggling to get hold of a wiring diagram. I have downloaded various LR workshop manuals but nothing that covers wiring. My obd2 port isn't working either, may just be a coincidence?
 
jimmacD said:
Does anyone have a wiring diagram for ignition, becm and ecu comms routes? Been busy with life.... fecking L322 threw a suprise spanner in the works with what I suspect is a failed timing chain guide.. totally out of the blue, started her up for School run and a bag of spanners rattles from drivers side front, ah bugger! She will have to sit until I have the pennies to repair, bit miffed as I had just serviced her and she was running great! Back to the P38, I have two weeks at home so have set a side the time to sort the old girl. I still feel as though the non start is due to Rodent/broken wire/poor earth somewhere but struggling to get hold of a wiring diagram. I have downloaded various LR workshop manuals but nothing that covers wiring. My obd2 port isn't working either, may just be a coincidence?
Click to expand...
Check fuse 33, it's 5amp in the under bonnet fuse box,it supplies power to the obd port.it powers a brown wire that runs in the loom under the expansion tank, through the bulkhead,under the heater to the port,there is a splice that powers the Hevac so if that's working I'd check the port,pin 16 is the power and pins 4&5 are ground.
 
tomcat59alan said:
Check fuse 33, it's 5amp in the under bonnet fuse box,it supplies power to the obd port.it powers a brown wire that runs in the loom under the expansion tank, through the bulkhead,under the heater to the port,there is a splice that powers the Hevac so if that's working I'd check the port,pin 16 is the power and pins 4&5 are ground. That's on my diesel,I think the petrol is the same
Click to expand...
Ta much for pointers, I am waiting on a fuse buddy (fooking Hermes, a week late) so I can systematically check all the fuses and their readings. The car was fine, left for a week, non start, bridged start relay as no signal from ignition... started fine, started fine with relay back in? Then nothing... tank pump is fine but no start signal getting to the ecu or relay?
 
jimmacD said:
Ta much for pointers, I am waiting on a fuse buddy (fooking Hermes, a week late) so I can systematically check all the fuses and their readings. The car was fine, left for a week, non start, bridged start relay as no signal from ignition... started fine, started fine with relay back in? Then nothing... tank pump is fine but no start signal getting to the ecu or relay?
Click to expand...
Any smell of burning in the fuse box?
 
tomcat59alan said:
Any smell of burning in the fuse box?
Click to expand...
Nope, had fuse box and ecu out to check for obvious.... corrosion/burning. Nothing else is effected in the car so I don't think it's a BECM fault, it's not immobilised... did an EKA entry to confirm. Car cranks OK, mahoosive tractor battery makes sure of that! One minute the car worked, then it didn't, then it did with a little hot wire and now it won't even hot wire! I think that it's not getting the ecu wake up message from the BECM... will tackle the ODB comms issue first though my Icarsoft diagnostic tool is a little basic with the P38, great on my L322 and Gaylander but limited access on anything older.
 
jimmacD said:
Nope, had fuse box and ecu out to check for obvious.... corrosion/burning. Nothing else is effected in the car so I don't think it's a BECM fault, it's not immobilised... did an EKA entry to confirm. Car cranks OK, mahoosive tractor battery makes sure of that! One minute the car worked, then it didn't, then it did with a little hot wire and now it won't even hot wire! I think that it's not getting the ecu wake up message from the BECM... will tackle the ODB comms issue first though my Icarsoft diagnostic tool is a little basic with the P38, great on my L322 and Gaylander but limited access on anything older.
Click to expand...
Most diagnostic tools are limited on the diesel version. The nanocom is the way for most.
You've bridged the fuel pump relay and the pump works?
 
tomcat59alan said:
Have you checked for power at the fuel cut off solinoid?
Click to expand...
Still trying to find the fuel cut off solenoid... supposed to be on to of the main fuel pump but can't find any electrics? I have lost the "glowplugs" light on the dash which makes me think that there is comms link problem effecting start/stop valve, glowplugs and injectors. These components are after the "start yer bugger!" signal and one or two not working wouldn't show as a complete non start? Could be very wrong? That's why I could really do with a wiring diagram.
 
Glowplugs could be your only issue if you're lucky, it won't start without them especially in the cold
 
jimmacD said:
Still trying to find the fuel cut off solenoid... supposed to be on to of the main fuel pump but can't find any electrics? I have lost the "glowplugs" light on the dash which makes me think that there is comms link problem effecting start/stop valve, glowplugs and injectors. These components are after the "start yer bugger!" signal and one or two not working wouldn't show as a complete non start? Could be very wrong? That's why I could really do with a wiring diagram.
Click to expand...
The solinoid is on the injector pump,try a search,I think @RangeRoller dt posted a photo but I may be wrong.there is a fuse link in the ECU box for the glow plugs,may be worth a look and a search for that.
 
tomcat59alan said:
The solinoid is on the injector pump,try a search,I think @RangeRoller dt posted a photo but I may be wrong.there is a fuse link in the ECU box for the glow plugs,may be worth a look and a search for that.
Click to expand...
My fusebuddy has arrived, just need it to stop raining and Wifey to watch some daytime telly so I can have a day tinkering with the old P38.... don't want to fix her too soon as Wifey will force me to sell! What is it with our Wives that we have to be the ones to sell stuff whilst they fill the wardrobes with shoes, clothes and shinny things!?
 
This do?
A55C9519-CC9C-4743-A369-8DFD5DBFE423.jpeg
 
jimmacD said:
Ta mucho! Are they tamper proof? Did a Citroen ecu swop and solenoid was coded, involved chisel and hammer before fitting a universal switch. Wondered if the P38 one could be hotwired?
Click to expand...

The stop solenoid is not coded or anything like that it is just an electric plunger, if you hold your finger on it and get someone else to turn the key you should feel it click, i had it on another members p38 and we swapped it out and hay presto it started and ran wear as before it would spin over and occasionally cough as if it was trying to start.
 
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