after using a boost starter on a 2012 LF45 the 30a ECU fuse (5 from the left of the top line of fuses) has blown…just blows straight away when trying a replacement fuse with ignition off…it didn’t start using the boost, just made a noise like a solenoid flickering
Warnings on the dash are Alternator warning and Engine warning (low air pressure + ABS too but those are normal with it sitting iirc).
Still turns over and all the lights/wipers/windows etc still work but doesn’t start.
Got an auto electrician coming out Monday but wondering what’s likely happened and if there’s anything I can check myself?
after using a boost starter on a 2012 LF45 the 30a ECU fuse (5 from the left of the top line of fuses) has blown…just blows straight away when trying a replacement fuse with ignition off…it didn’t start using the boost, just made a noise like a solenoid flickering
Warnings on the dash are Alternator warning and Engine warning (low air pressure + ABS too but those are normal with it sitting iirc).
Still turns over and all the lights/wipers/windows etc still work but doesn’t start.
Got an auto electrician coming out Monday but wondering what’s likely happened and if there’s anything I can check myself?
Cheers
You may have popped an ECU probably engine …What you can try if you follow the loom the plugs in to the NOX sensor back …roughly at the gearbox area it will connect in to a square plug,There will be 2 plugs and wrist slashing cable ties unplug the one for the nox sensor and see if the fuse pops ,if it is ok then a nox sensor will be required ,as a failed sensor brings on those warning and prevents it starting .but it has to be un plugged futher up the chassis as unplugging the sensor at the sensor won’t make any difference …But i would say you have popped the ECU
was hoping it could be something else that’d shorted but the ECU does sound like the culprit if that’s your first thought…
I can try checking the Nox sensor but would it blow the ECU fuse? First time I replaced the fuse was with the battery disconnected - when connecting the battery back up it was arcing/sparking between the lead+terminal then eventually blew the fuse, 2nd time I replaced the fuse with the battery connected and as soon as I tried to push it in there was blue flashes and it melted/burned the end of the fuse
what’s involved/a rough cost if it is the ECU?
after googling prices for new ecu are quite varied…it looks like need to change the key/barrel aswell as the ecu…does anything else need changed?
.Can you get the fuse number off the cover ? the code will be E then the numbers …It isn’t a good idea to fit a fuse with an active short as you may also burn out the terminals in the fuseboard …The best idea when checking for a short is to put a head lamp bulb where the fuse goes ,then when you find the short the bulb will significantly dull / go out …On your age of vehicle when we had the faults on the DIP that you have it was generally the NOX sensor and when we unplugged the plug futher up the chassis the vehicle would start…And independents couldn’t diagnoise it .It was one of those weird faults…Even if you have an spare sensor just plug it in …It will be the ECU or the sensor The fuse number may help as i can see what it controls .Feel free to PM as i would need the chassis number or reg to look up the vehicle details…Though LF diagrams are a nightmare
cheers - will have a look and get the number tomorrow - not 100% but I think it was the only ECU fuse that’s 30amp - the others were lower
not looking good tho - was speaking to a mechanic today asking about winding off the brakes (can’t tilt the cab fully where it’s sitting) and as soon as I mentioned that 30a fuse and using the boost starter he said ‘you’ve f’d the ECU’
just to update for completeness - yupp it was the engine ECU
independent guy came out, unplugged the ECU and reconnected the battery…fuse didn’t blow, so he supplied a used/recon? ECU and paired/coded? it to the truck
he did ask if he could take the old ecu…had no use for it and no intentions of trying to sell on ebay etc but I’m guessing he would try and repair it?
his total price wasn’t much more than the prices I can see advertised for repairing an ECU (might have went with that option after watching him taking it out etc) so was an unnecessary expense but could have been worse I suppose!