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Holden202T wrote:well you should be able to tell by the plug, if theres only 2 pins and plastic plug then i'd say no shielding.

Yep, there is only two pins in the plug but I thought the shielding may be earthed at the sensor end through the metal bolt down section however as Antus indicated it is not shielded.
Thanks

antus wrote:Yeah, the ebay add says:

Interchange Part Number: D1911A, D1927A, 6H1034, 7043

And thats the one we used.

To be clear, yes.. the abs sensor and plug wasnt shielded, but generally thats low on the engine and far enough away from the spark leads. We used the stock sensor, up to the connector, and cut it after the car side connector and attached to shielded cable we sourced at that point, and ran that the remainder of the way up to the module. This way if the sensor needs replacing an off the shelf VS/VT one can be swapped in from the plug down. The shielding may not have been needed, we were chasing a problem which turned out to be a bad module, but decided the shielding is probably a good thing anyway.

OK sounds good! I am offto order one.
Thanks

so the d1927a ignition module will work fine with out the shielding being grounded through the module it's self? as i also only have a 2 wire sensor

Always use a shielded cable for the sensor but only earth the shield it at one end. All the factory GM diagrams for the DIS module show it as a shielded cable too - first post of this thread has a pic.

Ok before installing the upgrade using a VX commodore ABS sensor, one last question (hopefully) before I install it I assume is there is a correct polarity for the ABS sensor (black and red wires) to the module A & C terminal is there a way to determine this or just trial and error?
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yes there is, i'm just trying to remember, i think with mine, when i had slots cut in the balancer the wires needed to be ass about, but with the toothed wheel the red is +ve and black negative.... i THINK!

VL400 told me that if the polirity is right when something goes near the sensor (ie tooth or slot) it should spike higher volts then go negative, if it goes negative then positive then its wrong polarity.

hopefully VL400 can confirm i have all this the right way round hehe

You can use a multimeter to work it out but you also do need to find out if the DIS module needs a rising and then falling or a falling and then rising signal.

To find out the polarity connect the sensor wires up to a multimeter. Get a screwdriver and place it on the sensor tip, as you remove it see what the meter reads. If you see a negative voltage then the lead connected to the positive of the meter will be the positive signal wire when using a toothed wheel and rising then falling signal. Swap the polarity for a slotted trigger wheel.

Holden202T and VL400 thanks for the responses, RE: "you also do need to find out if the DIS module needs a rising and then falling or a falling and then rising signal." ....I searched the net could not find anything any suggestions?

Given I have cut slots into the harmonic balancer I can now work out the polarity. Does it not matter whether it is rising or falling other than the timing being out by the number of degrees the width the cut/slot equals as this will be tuned out when trimming the reference angle to get the actual crank timing to match the software indicated timing Yes/No?

Also in OSE12P "Map A: set=Crank input active high" does this give the ability to fire on the rising or falling edge or is this flag setting referring to something else?

don't worry about it too much yet if your not sure. it'll run a lot better the correct way around so trial and error is an acceptable fall back plan (and how I did mine)

If the polarity is wrong, the trigger point will change as rpm increases which will tend to cause out to run pretty roughly