Favour from V6 owners

[cornishtaz]

I'm after a favour from V6 owners. I trying to establish whether I've got a knock sensor fault or wiring fault, I'd like the resistance readings of front & rear knock sensors and the resistance reading of the connections back to the ECU.

Thanks in advance

[cornishtaz]

Anyone

[RobbieV]

Not the sort of info many people would have i think !

Did you read through -

http://www.v6calibra.net/motonic/v6cali ... des.htm#16

http://www.v6calibra.net/common/v6calib ... sensor.htm

[MarkV6]

I can probably measure the resistance of the knock sensors for you tomorrow (once I get the bonnet up )

As for the wiring to the ecu the Ohms reading (resistance) should be zero (or as close as) Any wiring fault will show as a high resistance or off the scale if a broken wire.

Have you got ecu code 16 or 17 then??

[cornishtaz]

I've already read the V6calibra site

I've got code 17

The readings I've got are 1Mohm on both connectors back to the ECU(still connected) the rear knock sensor is open cct front one reads 1 ohm

[MarkV6]

the rear knock sensor is open cct front one reads 1 ohm

Rear knock sensor open circuit is your fault (breakdown in the circuit).
The resistance reading of 1M ohm on the front shows the front one is not at fault as it has a complete path for the electrical current.

Try swapping the connectors to see if you get TC16.

[cornishtaz]

I thought code 17 was for the front sensor or have I mis read the info on topbuzz

[MarkV6]

16 Knock sensor 1 (front engine cylinder bank)
No change in voltage, bad wiring or bad sensor

17 Knock sensor 2 (rear engine cylinder bank)
No change in voltage, bad wiring or bad sensor

V6Calibra.net/fault codes

I'm going by the bible...

[cornishtaz]

Ok nice one Mark will do some further checks tomorrow.

Just wanted to confirm the fault as I know the rear sensor is hard to get at.

[MarkV6]

Just wanted to confirm the fault as I know the rear sensor is hard to get at.

The wire runs behind the alternator mounting bracket as well. I found this out after I'd bolted everything on...

[§torm]

I guess you need a multimeter to do that, which I dont have unfortunately.

I suppose you could always check out a couple of our cars next Sunday? You're welcome to check the readings on mine if needed

[MarkV6]

Right, went to the car today with my trusty multimeter and this is what I got...

Front knock sensor wiring through ecu 1.01 MOhms
Front knock sensor o/c

Rear knock sensor wiring through ecu 1.00 MOhms
Rear knock sensor o/c

Seeing as I have no ecu codes, I can only conclude that a knock sensor with an open circuit reading is working ok.
Perhaps when the sensor picks up 'knock' then it completes the circuit and the ecu acts accordingly.

It has been reported that in some cases the front and back knock sensors are in the opposite order. In these cases a fault code 16 actually refers to the rear engine knock sensor (at back of engine back nearest windscreen). If unsure check by disconnecting each sensor in turn and driving as short distance to check which fault code has been triggered.

The only other path I can suggest is quoted above from V6.net, disconnecting one knock sensor at a time and seeing which codes get flagged by the ecu.

[RAINMAKER]

Is it possible to conclude that fault 17 can be the rear bank (bulk head) as after reading quite a lot of info yesterday on this it indicated 16 to be the front and 17 to be the rear..slightly confusing..

[cornishtaz]

Thanks Mark those readings really help and points to the front sensor as mine reads 1 ohm. Will do more checks tomorrow when I'm off work, hopefully get it sorted for next Sunday or its a no go for me.

[cornishtaz]

Just been out this morn and done some checks, I cleared all the faults codes by disconnectng the battery last night and confirmed this by flashing them this morn and none stored. I then disconnected the rear knock sensor ran the engine until ECU light came on and re-read the fault codes and got 16 and 17, cleared the codes again re-connected rear sensor ran engine until ECU light came on again read codes and got 17 so it looks like my front knock sensor is knackered. Vaux want £38 so will be going to autovaux, £23, and not use the car for the rest of the week(time to get the push bike out), and to think I had 2 of these before I moved house and they got mixed up with the crapin the old garage and now can't find them.

Thanks for everyones help.