Steve Rothwell answering your ENGINE MANAGEMENT queries
Diagnostic scanners
Q Can you advise what the relevance of the page listing a collection of vehicle manufacturers is in a scanner; is it necessary to select the manufacturer before the scanner will become functional for a given car? Thanks.
A The very basic scanners are normally set to just read EOBD codes from the diagnostic socket, and for these there is normally no vehicle selection needed. Once the scanners start to get a little more sophisticated, then they will acknowledge the slight differences used by the manufacturers and so by selecting the vehicle manufacturer on the start screen, it will ensure a correct translation of the hexadecimal codes that are retrieved from the engine control unit.
These units do normally also have an EOBD option on the start screen, and it is normally possible to select this to read off the codes, but selecting the manufacturer will give a better interpretation and will normally ensure the code is cleared correctly.
Brake pedal drops to the floor
Q My lad and I may have bitten off more than we can chew. The ABS, ESC and brake warning light came up the dash of his 2012 Hyundai i20 Active. Plugging in the Foxwell diagnostic tool we got C1210 right rear wheel sensor and C1604 ECU hardware error. A trawl of the internet came up with the ABS module (HECU) being at fault with the fix swapping out the failed unit. We purchased a preloved unit and spent the weekend wrestling the old one out and installing the used unit.
To bleed the ABS unit, we purchased a Foxwell NT630 and successfully bled the system with no signs of leakage. The operation of the ABS module went well with all solenoids firing into life and the pump whirring. Once all back together the brake pedal now just drops straight to the floor with little resistance and the two codes still persist. The brake master cylinder sounds odd with a sloshing sound when the pedal is operated. Could the master cylinder have been the issue all along causing low pressure in the system resulting in the brake warning light and ABS fault codes?
As a 19-year-old apprentice his budget to fix the problem is limited and we’re keen for the next fix to be the right one.
A On the photo you sent showing the screenshot of the codes you have, there was also a historic code of C1209 and this like the code which is showing as active (C1210) indicates a problem with the rear right (offside) speed sensor. The code C1604 does point to an internal ABS problem, but my first move would have been to test the rear right sensor to ensure that this was operating.
This is easily tested by disconnecting the multi-plug at the ABS unit and connecting an amme
