Obd2 K-line circuit

Then you need another ECU but to make it work a dedicated tester is needed to make it learn the security code otherwise it's immobilised

Even though this would be number 2 since it all began?

sierrafery said:

Then you need another ECU but to make it work a dedicated tester is needed to make it learn the security code otherwise it's immobilised

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Or Could It be a wiring issue potentially?

If you have comms with the ECM unplugged and you are sure it's a working ECM then it becomes complicated, eventually try to route a new K wire between the ECU plug and header and disconnect the old one to rule out a short circuit on that path

Copy I ran I new K-line wire But I can go back to my original gear and see if anything changes.

I had put a new pin in the 02 sensor ground so im thinking they may have caused the issue here. Just hoping I didnt fry two ECUs

Normally a short to ground on O2 sensor circuit should not ruin the ECU just throw a fault code, did you disconnect the original K line both sides

sierrafery said:

Normally a short to ground on O2 sensor circuit should not ruin the ECU just throw a fault code, did you disconnect the original K line both sides

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I did not. Although I spliced in very close. I know you said Voltages are irrelevant but I got a spar header as well as a spare ecu plug. I tried the new plug without splicing anything and was still receiving battery voltage on the kline plug directly out of the ECU

Continuity on the K-Line before and after were good as well all the way from the obd2 port up to the ecu plug

If you wired a new K line you have to cut the old one both sides otherwise you keep the short circuit there if you see what i mean so try that way

I'm thinking while unpluggin/plugging things in numerous times somethings changed in the wiring to one of the plugs to the ecu. Luckily that is the 1 thing Rave gives you when it comes to Voltages so tomorrow I could try to backprobe each and every pin to see if there is a issue with some of the voltages

sierrafery said:

If you wired a new K line you have to cut the old one both sides otherwise you keep the short circuit there if you see what i mean so try that way

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Like example, remove pin from ECU plug/ Header and wire directly to the pins with new wire?
Becuase I chopped both the ECU Side and Header side and spliced new 18g to the little piece that I had left from each pin
These Rover pins are a pain to reuse and I have no clue if I can buy new matching pins

Here is a Video I took from the Rover that was communicating.

And everything matches on mine minus the ECU Voltage thinking I may have jummed up the plug I put a new plug and still no matching Voltage

The working one shows something like 6.2 and mine shows 12.4

ATXOffRover said:

Like example, remove pin from ECU plug/ Header and wire directly to the pins with new wire?
Becuase I chopped both the ECU Side and Header side and spliced new 18g to the little piece that I had left from each pin
These Rover pins are a pain to reuse and I have no clue if I can buy new matching pins

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It's OK then as you deleted the old path so it's not in parallel with the new one, as long as you have comms with ECM unplugged and not with it connected and there is no chance of a short on the K line the probem is from the ECM, check all the earths to it to have good continuity from each black wire to body cos if one earth is missing the ECM can mix up the signal

sierrafery said:

It's OK then as you deleted the old path so it's not in parallel with the new one, as long as you have comms with ECM unplugged and not with it connected and there is no chance of a short on the K line the probem is from the ECM, check all the earths to it to have good continuity from each black wire to body cos if one earth is missing the ECM can mix up the signal

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Ok perfect I'm betting that may be the issue Ill check continuity to ground tomorrow and hopefully I find my problem. Thank you so much for your time man! You have no idea how nice it is to see that thing connect ( even without live data) After a week of trying to diagnose.

Also i dont quite understand what you are doing there in the video with those green wires cos the K line to ECM is pink and it's the only one relevant there, should be pin 20. Good luck, see you tomorrow

sierrafery said:

Also i dont quite understand what you are doing there in the video with those green wires cos the K line to ECM is pink and it's the only one relevant there, should be pin 20. Good luck, see you tomorrow

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Haha being at someones shop I wanted to make sure I didnt miss a thing. Was just making sure each and e very pin matched. I have a hard time with the Rave Electrical Diagrams so just wanted to cross my T's and dot my I's haha

Another thing i forgot to ask, is that vehicle cranking and starting? cos if you unplugged the ECM with battery connected or even worst with ignition on it can go to immobilised status and then when you connect the ECM it disables the diagnostic link. Keep in mind that never unplug or reconnect the ECM or BCU with battery connected. You can reconect the battery once the ECU is removed or completely reconnected. Eventually if you did that give an unlock command with the fob to remobilise it

sierrafery said:

Another thing i forgot to ask, is that vehicle cranking and starting? cos if you unplugged the ECM with battery connected or even worst with ignition on it can go to immobilised status and then when you connect the ECM it disables the diagnostic link. Keep in mind that never unplug or reconnect the ECM or BCU with battery connected. You can reconect the battery once the ECU is removed or completely reconnected. Eventually if you did that give an unlock command with the fob to remobilise it

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Yeah the Engine cranks over and runs all day fine. So I checked continuity for ground to body earth and got good contact with pin 4, 5, and 6 on plug co634. Every other ground was incluclusive. Cleaned everything with contact cleaner and put back together and up turning key to position 2 had flashing M & S Lights pulled apart the EAT ECU Cleaner put back and still Flashing lights. Cranked up and they went away immediately guessing it was a Voltage fault. Went back to Main ECU K-line that remains Disconnected and was getting roughly 13.5 V with the vehicle running. Not Sure if I should be able to run a continuity check and RH and LH Earths or if its switched on mind you all these continuity checks were done with battery neagative disconnected. Ill be on and off today gotta go work on LS boat motors now haha

I’ll just run a a continuity check from neg battery lead while it’s disconnected to all ecu grounds and see what I can come up with. If you have any other options to check let me know. I’m guessing some of them aren’t actual body grounds.