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Hi, we believe the immobiliser is disarming, everything seems to be right when the code is punched in. Thanks for the tip of putting an led (with protective resistor across the injector, to see if they are being triggered. We will give that a go. Cheers…Derek
Thank you for this, very helpful. Peter has just told me one of the rubber seals on one of the injection rails is split. You wouldn’t know where to source them from would you? Cheers…Derekxantia_v6 wrote: ↑Mon Aug 08, 2022 7:56 pmI don't know if you have seen and deciphered the diagrams attached to viewtopic.php?f=8&t=10268&p=122537&hili ... 9e#p122537
I think there were some other Fenix3 diagrams posted on this site, but I cna't immediately find them.
Thank you for such a comprehensive and informed response, I am sure this will be of enormous help. There is always a chance that an earth has gone bad but I did replace those strange earth blocks/fittings many years ago, with direct earth bolts and eyes. The other thing is there was an old mouse nest under the bonnet when the XM was pulled out, so I hope the buggers haven’t been chewing the wiring? Thanks again, I will report back when the big lump bursts back into life…DerekDieselman wrote: ↑Tue Aug 09, 2022 6:35 amFenix-3 diagram is in the linked topic. I believe you have already had this.
viewtopic.php?f=8&t=10268
The injector seals are just o rings and are commonly available, yours should be Seimens Dekra 2892 injectors.
The power for the injectors is fed via relay 807, which feeds power to the Ecu and ignition amplifier, so must be working.
The injectors are fed via a single =12v power feed and returned to the Ecu in two Gnd feeds.
Use a +12v test lamp to check for power feed and to see if the returns are shunting to Gnd.
The injectors should have resistance of ~16 Ohms, hot, or cold, thus a test lamp upto 9w would be sufficeint to test the injector voltage.
You could perform a physical check on the injectors by pressurising them with fuel (3 Bar), then if they have +12v, shunt the return side to Gnd and watch the injector spray.
This Ecu doesn't emply sequential injection, it fires them in each bank, so a quick shunt to Gnd of the return wires should make ht eengine run, if not properly.
Check all power feeds and Gnds for the Ecu and actual fuel pressure at the rail.
I would be surprised if the Ecu jhas failed just for injector trigger, they are pretty reliable, I suspect the power feed wire is the issue.
If there is a reliable, timed, spark, then the crank sensor must be functioning, if not suspect the sensor has failed. It should have 300 ohms resistance.
Sorry, stupid question, do you know the location of relay 807? Cheers…Derekdcz1643 wrote: ↑Tue Aug 09, 2022 7:17 amThank you for such a comprehensive and informed response, I am sure this will be of enormous help. There is always a chance that an earth has gone bad but I did replace those strange earth blocks/fittings many years ago, with direct earth bolts and eyes. The other thing is there was an old mouse nest under the bonnet when the XM was pulled out, so I hope the buggers haven’t been chewing the wiring? Thanks again, I will report back when the big lump bursts back into life…DerekDieselman wrote: ↑Tue Aug 09, 2022 6:35 amFenix-3 diagram is in the linked topic. I believe you have already had this.
viewtopic.php?f=8&t=10268
The injector seals are just o rings and are commonly available, yours should be Seimens Dekra 2892 injectors.
The power for the injectors is fed via relay 807, which feeds power to the Ecu and ignition amplifier, so must be working.
The injectors are fed via a single =12v power feed and returned to the Ecu in two Gnd feeds.
Use a +12v test lamp to check for power feed and to see if the returns are shunting to Gnd.
The injectors should have resistance of ~16 Ohms, hot, or cold, thus a test lamp upto 9w would be sufficeint to test the injector voltage.
You could perform a physical check on the injectors by pressurising them with fuel (3 Bar), then if they have +12v, shunt the return side to Gnd and watch the injector spray.
This Ecu doesn't emply sequential injection, it fires them in each bank, so a quick shunt to Gnd of the return wires should make ht eengine run, if not properly.
Check all power feeds and Gnds for the Ecu and actual fuel pressure at the rail.
I would be surprised if the Ecu jhas failed just for injector trigger, they are pretty reliable, I suspect the power feed wire is the issue.
If there is a reliable, timed, spark, then the crank sensor must be functioning, if not suspect the sensor has failed. It should have 300 ohms resistance.