Drama with AFM or so I thought
18 July 2002, 12:32 PM
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I bought a Dawes AFM from Jamie the other week and had it fitted by an Auto Electrician, as my mate was busy and I didn't have the time. I noticed straight away that it wasn't working correctly (as I had the same model a while ago, in my MY00) and they weren't the same (i.e. Red on WOT with lambda voltage greater than 900 millivolts)
After doing various checks, including reading the lambda sensor with a select monitor and delta dash, came to the conclusion the Dawes AFM was knackered. This was after re-soldering all the connections that the Auto Electrician hadn’t done
Contacted Jamie (and kicked off) and he said that they have never had a problem before with one, and could I perform a few tests. I told him that I had (I remember being pissy with him) and could he just send me another ASAP.
He agreed and when it arrived yesterday imagine my surprise, when I connect the AFM, and it did the same
The thing that threw us earlier in the week was the Lambda O2 sensor was reporting the correct voltage on the Delta Dash software. Measuring the voltage (at the lambda, and burning my arm on the downpipe) a voltmeter confirmed this. When measured at the ECU connection point (signal wire to ground) the voltage was the same as the delta dash was reporting (as we were using a different earth) It was so confusing, I think on reflection where the Auto Electrician went wrong was they found an earth and didn't check the impedance to ground (with the ignition on) Instead of the DC loop resistance to earth being 2 ohms or thereabouts with ignition off, when the ignition was switched on the loop resistance went to 40 ohms, so this wire must have been a sensor earth or something.
After all this drama we had I would strongly recommend that the +12 and earth connections should come from the battery and not from the ECU. You can find a good earth and +12 volt supply from the ECU, but it isn't easy
So the post that Darren Dawes made the other week (that I didn't agree with at the time) I would agree with now There are a lot of people out there that could fall into the trap that the Auto Electrician did (they are supposed to be experts)
We tested both meters in parallel with each other at just below and above the trigger voltages and were amazed at how accurate the meters were. The other amazing thing was how closely matched they were (infact there wasn't a difference between them) Darren must have come cool calibration equipment to be able to do this. You'd expect this kind of accuracy in an expensive AFM meter, but not for £50.
Anyway thought I give you some positive feedback! And thanks Jamie for the excellent service and product……I now have to return a perfectly good AFM with egg on my face, and pay for the postage
Cheers Phill C
PS I wouldn’t blame Jamie putting me in the c**t book, lol….
After doing various checks, including reading the lambda sensor with a select monitor and delta dash, came to the conclusion the Dawes AFM was knackered. This was after re-soldering all the connections that the Auto Electrician hadn’t done
Contacted Jamie (and kicked off) and he said that they have never had a problem before with one, and could I perform a few tests. I told him that I had (I remember being pissy with him) and could he just send me another ASAP.He agreed and when it arrived yesterday imagine my surprise, when I connect the AFM, and it did the same
The thing that threw us earlier in the week was the Lambda O2 sensor was reporting the correct voltage on the Delta Dash software. Measuring the voltage (at the lambda, and burning my arm on the downpipe) a voltmeter confirmed this. When measured at the ECU connection point (signal wire to ground) the voltage was the same as the delta dash was reporting (as we were using a different earth) It was so confusing, I think on reflection where the Auto Electrician went wrong was they found an earth and didn't check the impedance to ground (with the ignition on) Instead of the DC loop resistance to earth being 2 ohms or thereabouts with ignition off, when the ignition was switched on the loop resistance went to 40 ohms, so this wire must have been a sensor earth or something.
After all this drama we had I would strongly recommend that the +12 and earth connections should come from the battery and not from the ECU. You can find a good earth and +12 volt supply from the ECU, but it isn't easy
So the post that Darren Dawes made the other week (that I didn't agree with at the time) I would agree with now There are a lot of people out there that could fall into the trap that the Auto Electrician did (they are supposed to be experts)We tested both meters in parallel with each other at just below and above the trigger voltages and were amazed at how accurate the meters were. The other amazing thing was how closely matched they were (infact there wasn't a difference between them) Darren must have come cool calibration equipment to be able to do this. You'd expect this kind of accuracy in an expensive AFM meter, but not for £50.
Anyway thought I give you some positive feedback! And thanks Jamie for the excellent service and product……I now have to return a perfectly good AFM with egg on my face, and pay for the postage
Cheers Phill C
PS I wouldn’t blame Jamie putting me in the c**t book, lol….
18 July 2002, 12:38 PM
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LOL Cheers Phil but you're ok cos the book is jam packed this week!
I'm happy to help and even more stoked with the results!
Jamie
www.j-w-raciong.com
I'm happy to help and even more stoked with the results!
Jamie
www.j-w-raciong.com
19 July 2002, 09:00 AM
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I run a Dawes AFR and I bought it with standard Dawes adjustment (not the specific Scooby set up)I have adjusted it my self ( to the scooby spec.) and can confirm that you need to be take care with the earth connection, use the battery or be sure you have zero ohms from the connection you use to battery ground ( both wih injection off and on.
For the 12 V supply just find a vacant 12V lead. I had constant reading on the Dawes with a supply voltages from 5V to 14V so no need to take special care here.
You need to use a high resistance Volt meter e.g. a quality Digital meter, to measure the Lamda signal. A normal Volt meter will put load on the lamda signal and show a to low voltages.
For the 12 V supply just find a vacant 12V lead. I had constant reading on the Dawes with a supply voltages from 5V to 14V so no need to take special care here.
You need to use a high resistance Volt meter e.g. a quality Digital meter, to measure the Lamda signal. A normal Volt meter will put load on the lamda signal and show a to low voltages.
19 July 2002, 02:00 PM
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Well it all sorted now But am well pissed off the the auto electrician and am making a claim through my CC company
I did source the +12 and earth from the ECU, but as said above make sure you test the connection before connecting it up with and without ignition on
We had two digi volt meters as we were question everything
Cheers Phill C
But am well pissed off the the auto electrician and am making a claim through my CC company I did source the +12 and earth from the ECU, but as said above make sure you test the connection before connecting it up with and without ignition on
We had two digi volt meters as we were question everything
Cheers Phill C
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