RSM ecu wiring harness
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Veniston hehehe did you change your opion before or after Red and my SUBLIMINAL messages? LOL! smile.gif hehehehehe
Mabye i'll be the first with the RSM-GP and hopefully contribute to TSR with a worthwhile howto wink
[ April 26, 2002, 11:34 AM: Message edited by: Decker ]
Mabye i'll be the first with the RSM-GP and hopefully contribute to TSR with a worthwhile howto wink
[ April 26, 2002, 11:34 AM: Message edited by: Decker ]
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From: Rancho Palos Verdes, CA
Vehicle: 2008 Toyota Prius 2006 Suzuki SV650S
QUOTE
Red:
APEXi explicitly outlines that the part should be grounded TO the ECU, so follow their directions. There is a good reason for it -- the same reason why the two grounds on the S-AFC must A: be grounded to ECU and B: must be SEPERATELY conencted but still go to the same wire.
Wierd I know, but just follow the directions
I dont see a reason why you should have to ground anything out to the ECU ground. APEXi explicitly outlines that the part should be grounded TO the ECU, so follow their directions. There is a good reason for it -- the same reason why the two grounds on the S-AFC must A: be grounded to ECU and B: must be SEPERATELY conencted but still go to the same wire.
Wierd I know, but just follow the directions
ANY ground should suffice. Using a NON-ECU ground will also protect the ECU from possible damage. I'm not saying the unit ain't cool, or nice...but I just don't see any point behind risking your ECU when it's not 100% necessary.
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The reason is because of ground loop isolation, and it's a problem much more "obvious" to the casual viewer when talking about very high powered stereo equipment.
Let's say you're installing a huge stereo in your car. You're using a line-level only three channel 8v RCA deck, a standalone three channel crossover, two amplifiers and eight total speakers (2 tweets, 4 full ranges, 2 subs) off those amps. And let's say you're gonna run about 800w RMS total power.
Well, here's the deal. When doing a professional installation like this, you WANT to use a common ground as much as possible. This means that, if at all possible, both amps and the crossover will use the exact same chassis ground strap. If it's possible, even the DECK should use the same ground strap. Otherwise in high power situations, the disparate grounding points can actually cause an audible "hum" -- also known as a ground loop".
Ground loop is a small amount of voltage distortion caused by slight variations in resistance between two grounding points in a common electrical system. When you've got a high-powered stereo, it can be heard as a hum because the distortion is being amplified greatly.
In a very high-precision electrical system (your ECU and associated equipment), while the distortion is still fairly small, the voltage drop across the ECU ground versus a "nearby" chassis ground can be VERY large (when considering the very small voltages your ECU processes)
The reason you ground the S-AFC and other such tightly-coupled devices directly to your ECU ground is because you are eliminating ground loop issues. They may not seem like much, but they can cause all kinds of problems with small-voltage high speed electronics.
Ground loop problems in this scenerio would result in rough running, inconsistant results and even heat problems with the IC's dealing with inconsistant signal. These precautions should be taken for any S-AFC, RSM-GP, S-ITC or similar device that directly intercept and then modify sensor readings to the ECU.
Let's say you're installing a huge stereo in your car. You're using a line-level only three channel 8v RCA deck, a standalone three channel crossover, two amplifiers and eight total speakers (2 tweets, 4 full ranges, 2 subs) off those amps. And let's say you're gonna run about 800w RMS total power.
Well, here's the deal. When doing a professional installation like this, you WANT to use a common ground as much as possible. This means that, if at all possible, both amps and the crossover will use the exact same chassis ground strap. If it's possible, even the DECK should use the same ground strap. Otherwise in high power situations, the disparate grounding points can actually cause an audible "hum" -- also known as a ground loop".
Ground loop is a small amount of voltage distortion caused by slight variations in resistance between two grounding points in a common electrical system. When you've got a high-powered stereo, it can be heard as a hum because the distortion is being amplified greatly.
In a very high-precision electrical system (your ECU and associated equipment), while the distortion is still fairly small, the voltage drop across the ECU ground versus a "nearby" chassis ground can be VERY large (when considering the very small voltages your ECU processes)
The reason you ground the S-AFC and other such tightly-coupled devices directly to your ECU ground is because you are eliminating ground loop issues. They may not seem like much, but they can cause all kinds of problems with small-voltage high speed electronics.
Ground loop problems in this scenerio would result in rough running, inconsistant results and even heat problems with the IC's dealing with inconsistant signal. These precautions should be taken for any S-AFC, RSM-GP, S-ITC or similar device that directly intercept and then modify sensor readings to the ECU.
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just an update. wink
got it installed worked fine but didn't read my speed got a big fattie 0 smile.gif found out that I hooked one of the s-afc's cables into the speed splice I had sad.gif Now I figured out what those other cables on the s-afc were. They were just part of a standard harness that apexi sellx, they aren't connected to anythign wink hehehe, anyway, got it fixed and works beautifully wink Check out my post
got it installed worked fine but didn't read my speed got a big fattie 0 smile.gif found out that I hooked one of the s-afc's cables into the speed splice I had sad.gif Now I figured out what those other cables on the s-afc were. They were just part of a standard harness that apexi sellx, they aren't connected to anythign wink hehehe, anyway, got it fixed and works beautifully wink Check out my post
