4WD stopped working
4WD stopped working
Hi everyone. I have a 2015 sx dmax auto. Recently it would randomly have the traction control light and check 4wd light show up on the dash when driving. It was intermittent and seemed to be no consistently to how long it stayed on for or when it would come on. Recently upon start up, the 4wd symbol on the dash flashes and beeps for about 15secs, the light disappears and the traction control and check 4wd light come on and stay on. 4wd will not engage at all now, turn the switch has the same result as the start up. Twice now when on concrete, turning sharp and slowly it feels like 4l has all of a sudden engaged and it needs the extra grunt to get through the turn, after a minute its fine again. Have seen on other forums battery issues causing the check 4wd light but battery is good, terminals and connections good, can't find a fuse that is blown. Thinking electrical due to the intermittent way it went. however desperate for any other ideas to investigate. Local auto electricians and mechanics apparently have no available time to fault find for approximately a month.
Re: 4WD stopped working
gacre86
Just because the battery may be ok doesn't mean the cranking voltage is ok. Has the Cranking, load and holding voltage, been checked? You may think it is but it may drop the voltage below the ECU threshold voltage when cranking.
Also, the battery to chassis and body earthing lugs/loops might be dirty and acting as if the battery cannot supply. Many systems will indicate "inability to function: because the ECU has detected lower than the ideal at startup.
Even if the system is sound, the starter motor may be drawing more current than normal and causing the voltage to be dragged lower because of it's increased drain. Increased drain can be for two reasons. Bushes/bearings/and planetary gearing may be dry and using lots more current. The brushes of the starter may have deposited their very conductive wear dust between brush holder and negative of starter. That causes direct partial shorting to negative and vastly increases the load on the starter as the battery energy is not going to the field and armature as designed, but straight to negative.
If the ABS light has come on or Traction control too, that system use sudden high current to run it's hydraulic brake pump motor, and so, if a low voltage condition has registered in ECU which might be caused by dirty, loose, damaged, partially fractured cabling fractured or dragging starter it will show a fault. This is to guard against you NOT HAVING ABS or Traction control working in an emergency, or at least alerting you something is wrong. Body earths for some systems can look OK but not carrying the required current when asked for.
Your ABS unit has thick wires to its motor, 12v feed and an earth somewhere. The earth to neg must be a good connection.
My immediate guess is one or more body earth lugs are not clean and working as intended. Fairly easy to check those.
Hope this assists.
Just because the battery may be ok doesn't mean the cranking voltage is ok. Has the Cranking, load and holding voltage, been checked? You may think it is but it may drop the voltage below the ECU threshold voltage when cranking.
Also, the battery to chassis and body earthing lugs/loops might be dirty and acting as if the battery cannot supply. Many systems will indicate "inability to function: because the ECU has detected lower than the ideal at startup.
Even if the system is sound, the starter motor may be drawing more current than normal and causing the voltage to be dragged lower because of it's increased drain. Increased drain can be for two reasons. Bushes/bearings/and planetary gearing may be dry and using lots more current. The brushes of the starter may have deposited their very conductive wear dust between brush holder and negative of starter. That causes direct partial shorting to negative and vastly increases the load on the starter as the battery energy is not going to the field and armature as designed, but straight to negative.
If the ABS light has come on or Traction control too, that system use sudden high current to run it's hydraulic brake pump motor, and so, if a low voltage condition has registered in ECU which might be caused by dirty, loose, damaged, partially fractured cabling fractured or dragging starter it will show a fault. This is to guard against you NOT HAVING ABS or Traction control working in an emergency, or at least alerting you something is wrong. Body earths for some systems can look OK but not carrying the required current when asked for.
Your ABS unit has thick wires to its motor, 12v feed and an earth somewhere. The earth to neg must be a good connection.
My immediate guess is one or more body earth lugs are not clean and working as intended. Fairly easy to check those.
Hope this assists.
Re: 4WD stopped working
"randomly have the traction control light and check 4wd light show up on the dash when driving."- check all earths and break, clean with contact cleaner, then remake every connection you can find associated with the 4WD and traction control systems, including the wiring to the wheel sensors.
If you have a code reader that will read more than engine codes check for these,
If you have a code reader that will read more than engine codes check for these,
Re: 4WD stopped working
Re reading your initial post indicates to me a possible fault source.
Seeing modern electronics are initiated by a button press, ie, pressing for H4 or then L4, it is only a momentary contact of the switch which selects or deselects a function.
That process is called "toggling", ie, from one state to another. Therefore, if the voltages in the system are being varied beyond the circuit tolerance value by dirty wiring or Low startup voltage, the system may switch between on and off at any stage of use. IS the alternator providing constant controlled output at or near to 14.0 -14.4 while under a normal load? Check alt voltage and if battery voltage return to normal quickly after startup. Alt could be low on regulated voltage and/or a diode in the alt may have blown and although near normal voltage may be reached, the output will be around 1/3 of what it should be and so not charging battery fully.
Seeing modern electronics are initiated by a button press, ie, pressing for H4 or then L4, it is only a momentary contact of the switch which selects or deselects a function.
That process is called "toggling", ie, from one state to another. Therefore, if the voltages in the system are being varied beyond the circuit tolerance value by dirty wiring or Low startup voltage, the system may switch between on and off at any stage of use. IS the alternator providing constant controlled output at or near to 14.0 -14.4 while under a normal load? Check alt voltage and if battery voltage return to normal quickly after startup. Alt could be low on regulated voltage and/or a diode in the alt may have blown and although near normal voltage may be reached, the output will be around 1/3 of what it should be and so not charging battery fully.