2006 golf mk 5 1.9 tdi engine code bkc 103hp

[mr steve t]

Hi everybody. This vehicle has oil low pressure warning light coming on above 1500rpm. I believe instrumentation is incorrect and possible electrical fault. oil pressure has been checked and ok and engine runs noise free.Oil pressure switch has been renewed also. Still no different. Anybody had this same fault and managed to fix it? would be gratefull of any ideas or clues.

[Sam]

Welcome to VWAF

[SammoVWT]

Hi everybody. This vehicle has oil low pressure warning light coming on above 1500rpm. I believe instrumentation is incorrect and possible electrical fault. oil pressure has been checked and ok and engine runs noise free.Oil pressure switch has been renewed also. Still no different. Anybody had this same fault and managed to fix it? would be gratefull of any ideas or clues.

Welcome.

If it has been pressure checked with gauges and confirmed ok, with a new pressure sensor fitted also - I would suggest that your wiring loom to the sensor/plug is broken. Inspect the wiring for any broken insulation/shorts, or get an extra body to move the wiring to see if the light goes out.

Clean out the plug with contact cleaner also incase of corrosion/oxidation. The light is working so thats good point.

Just be 100% sure the pressure is correct at 1500 rpm and you arent getting a low pressure oil starvation situation.

[mr steve t]

Thanks for that. Would i be right to assume the same light and warning would come on if its open circuit as well ? fault seems to be there even if the oil pressure switch wire is removed. engine has to be running above 1500rpm though which seems a bit odd.

[SammoVWT]

From a logical point of view I would have thought a closed circuit would be a healthy one, hopefully someone else can confirm. But you may have to post in the correct section for that. Just make sure your voltages are okay, so its not an electrical issue from some lack of charge or drain.

I've had wonderful things happen with dash lights and low battery charge in the past

[mr steve t]

The fault is still there even when the oil pressure wire is disconnected but still has to be run above 1500rpm before warning comes on. very strange as in theory it cant be knowing what the pressure is if switch is not connected.

[mr steve t]

Will have to try get the vehicle back but at the time it was in,we scanned it and nothing showed up and no evidence on live readings that suggested battery voltage or charging system not functioning. some forums had suggested known crank sensor faults had spiked the oil pressure warning system and to be honest the items both have their wiring harness in the same sub trunking for about a foot. we did replace crank sensor with new vw genuine. (spas job for access). still no different.

[SammoVWT]

On my old beast, the pressure switch is wired to the dash as an idiot light and seperate to the ECU regulation, not sure if this is the same on newer models