Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: Skint on 30 May 2010, 18:19:41

Title: Sensor problems and the Engine Warning light
Post by: Skint on 30 May 2010, 18:19:41
I have done the paper clip test and retrieved the codes X20XEV 1996 Simtec 56.0/56.1 (codes from www.Topbuzz.co.uk)
(each repeated 3 times)
12 - Initiation
13 - Oxygen Sensor Open Circuit
71 - Intake Air Temperature Sensor Voltage High
92 - Camshaft Sensor Incorrect Signal
12

I understand I maybe able to take readings (using a multimeter) from some sensors to establish if they are faulty, does anyone know what the tests are and what readings I should expect for any of the above?

I have done a quick google and not found exactly what I was looking for, just tantalising hints.

Not happy about the Camshaft Sensor, this will be the second one I have replaced and I know that this car had at least one replaced by my father.

I am thinking that the oxygen sensor and air temp might help explain why it struggles with emissions. I need to trace the oxygen sensor cables to determine if they are intact.

I am also having problems with over heating and my air temperature sensor reading silly numbers. The garage said my fan does not activate (they said it was seized) although it runs rough when 12 volts is applied to the terminals it does spin. Is there any measurements I can take off the Water temperature sensor (mounted on the radiator) to determine if its faulty? (I did not get either fault codes 14 or 15 reported)
Might these be related to any of the other problems?
Title: Re: Sensor problems and the Engine Warning light
Post by: RobG on 30 May 2010, 18:25:40
Were cam sensors genuine from VX
Title: Re: Sensor problems and the Engine Warning light
Post by: Skint on 30 May 2010, 18:27:16
I am not sure about the one my father replaced, the one I replaced was not from vx but was of the same original manf but the logo had been obliterated but still recognisable in part.
Title: Re: Sensor problems and the Engine Warning light
Post by: RobG on 30 May 2010, 18:29:26
Quote
I am not sure about the one my father replaced, the one I replaced was not from vx but was of the same original manf but the logo had been obliterated but still recognisable in part.
Don`t even think about replacing any of the sensors with aftermarket, I suspect that`s why you`re getting the 92 again
Title: Re: Sensor problems and the Engine Warning light
Post by: Abiton on 30 May 2010, 19:52:40
With regard to the 'sensor' on the radiator, I think you'll find that's not a sensor as such, but a pair of thermoswitches.  They simply close contacts at two different temperatures, which via a relay/relays switch the radiator fan on automatically at the speed appropriate to the temperature.  So below maybe 95(?)°C neither switch will be closed and the fan will not operate, above this (guessed) temperature one of the switches will 'make' and trigger the fan to come on at low speed.  If the temperature still doesn't come down, the other switch will close at maybe 100°C and bring the rad fan up to full speed. 
Should be able to test it by getting the car up to the temperature where you'd expect the fan to be on, unplug the connector from it, then measuring for continuity between the pin the brown wire was connected to and each of the others.
The wiring diagram is a bit complex in this area so I can't guarantee that there isn't more to it.

The sensor that tells the ECU the engine temperature is the one that gives the fault codes you mention if bust, that's at the rear of the head of the engine.  Don't think that one can switch the rad fan on, or fail to if broken.

Edit: If the fan runs rough, as you say, it may well have blown a fuse due to pulling too much current.  This seems more likely than a failed radiator thermoswitch TBH.

Don't think the overheating will be causing any of the other fault codes, but the faults that are causing those codes may affect engine temps, maybe.