AEM 30-0300 WB S_AUJP not reading right.

I am using S_AUJP V6 and have WB on Pin F14. Ground on Sensor Gnd, should it be on ECU Gnd? System is seeing WB but reading is not agreeing with gauge.

Have
WB OPT 1 (0x99A), b6 = AEM Linear AFR selected.
WB OPT 1 (0x99B), b7 - Sensor #1 PIN (0=F14; 1=A3) set at 0 for Pin F14

This is listed in Description of WB2 AFR-Sensor #1 of the ADX

L01C5 = WB AFR1
***VERY IMPORTANT***
YOU MUST ENTER THE CONVERSION EQUATION FOR THE WBo2 CONTROLLER BEING USED.
- If using an internally-supported controller,
the AFR Conversion Equation is: X / 10
- If using another controller, refer to
WBo2 Conversion Equations in the supplied
documentation.
***VERY IMPORTANT***

I have tried X/10 and the equation listed in the doc = (0.0464*X) + 7.3124
I have also tried the equation given by AEM (2.3750*X) + 7.3125

Readings still not agreeing.

Thanks
Chuck

Tried several things and formulas. Moved signal ground to ECU ground from sensor ground. Checked readings against voltage signal, voltage agreed with gauge.

Couldn't get it closer then about 2AFR points but seemed linear. So I just added a - to the equation and ended up with (x/10) - 1.73. This gets me close.

Quote:

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Originally Posted by MG-Maxx

Tried several things and formulas. Moved signal ground to ECU ground from sensor ground. Checked readings against voltage signal, voltage agreed with gauge.

Couldn't get it closer then about 2AFR points but seemed linear. So I just added a - to the equation and ended up with (x/10) - 1.73. This gets me close.

---

:thumbsup:

dave w

Check that your WbO2 counts is equal to you measured voltage as a start. The conversion from counts (0-255) is to multiply counts by 0.0195 and that should put you within a few .01 of your voltage.

The ADX has this statement under WB02 Sen1 counts

L01C5: Provides Counts if using a controller not internally-supported (default)

0x0034: Provides Counts If using one of the 7 S_AUJP internally-supported controllers

If using an internally-supported controller, to report Sensor #1 Counts the address "0034" must be entered into one of the 63 ALDL Reporting Scalars. The Packet Offset decimal value here will be 1 less than the number of the selected ALDL Reporting Scalar. DO NOT use ALDL Reporting Scalar #37 as that will be reporting Sensor #1 AFR.
If using other than an internally-supported controller, the value '36' decimal is already entered as the Packet Offset to report Sensor #1 Counts from the address '01C5' per ALDL Reporting Scalar #37.

37 does have 01C5 in it. Do I change this or use #38 which I am not using? What would I put in there.

or should I go ahead and set it up for Lamda?

I am using a supported WB.
Thanks for any assistance.
Chuck

0034 looks like the correct value for counts and if I am understanding the way the system works you should be able to put it in #38 if you are not using it. You will have to modify the multiplier in your adx file

There are two grounds for that WB. One is a power ground, black, and should be connected to the engine where the ECM is grounded (tying into the ECU ground nearer the ECM is also ok), and there is a brown analog ground, that should be connected to the sensor ground. IIRC there are two sensor grounds and one MAY work better than the other, since they might be isolated in ternally and be paired with different inputs.

As you've found sometimes you need to use either a different setting than you thought, or custom formula to get the AFR reading correct.