Hey guys! I'm currently working on a customers Supra (which just so happens to be my old car...) and I'm installing an AEM EMS v1. P/N 1130-031. I'm attempting to hook it up via speed density, but I'm having some issues.
The IAT sensor is easy, 2 wires, wired into two pins on the old AFM plug. Easy and done, polarity does not matter.
The MAP sensor is not so easy. Well, it is, but it isn't. 3 wires, 5v reference, sensor ground, and the MAP output. Through my research, I've found that these wires go to pins 3C, 4C, and 17A, respectively. Now, here's where my question lies. When the AEM was new, they included the C connector into the ECU, as the Toyota harness only has the A, B, and D connectors. (i'll post up the installation instructions at the end of this post and this will all make a little more sense. So, I cannot use pins 3C and 4C. Can I connect these two wires to any other 5v sensor reference and ground? Is there a difference between a sensor ground and a chassis ground?
Heres my thought. Hook up the MAP sensor output to pin 17A, already done. Then hook up the 5V reference to pin 1B, and hook up the sensor ground to pin 9B. Thoughts? This SHOULD work as its just a ground and 5V, but I've never installed an EMS before, let alone wired it for speed density. Let me know what you think!
View attachment 10-1130 for EMS - 30-1130.pdf
EDIT: I just did a quick search on eBay for the plug I'm missing, and came across a Honda EMS. IIRC (its been years since I've dealt with this stuff), don't certain Hondas use the same ECU plugs as our Supras? If so, could I potentially find the correct plug off a certain Honda in a junk yard? If it came down to that of course.
The IAT sensor is easy, 2 wires, wired into two pins on the old AFM plug. Easy and done, polarity does not matter.
The MAP sensor is not so easy. Well, it is, but it isn't. 3 wires, 5v reference, sensor ground, and the MAP output. Through my research, I've found that these wires go to pins 3C, 4C, and 17A, respectively. Now, here's where my question lies. When the AEM was new, they included the C connector into the ECU, as the Toyota harness only has the A, B, and D connectors. (i'll post up the installation instructions at the end of this post and this will all make a little more sense. So, I cannot use pins 3C and 4C. Can I connect these two wires to any other 5v sensor reference and ground? Is there a difference between a sensor ground and a chassis ground?
Heres my thought. Hook up the MAP sensor output to pin 17A, already done. Then hook up the 5V reference to pin 1B, and hook up the sensor ground to pin 9B. Thoughts? This SHOULD work as its just a ground and 5V, but I've never installed an EMS before, let alone wired it for speed density. Let me know what you think!
View attachment 10-1130 for EMS - 30-1130.pdf
EDIT: I just did a quick search on eBay for the plug I'm missing, and came across a Honda EMS. IIRC (its been years since I've dealt with this stuff), don't certain Hondas use the same ECU plugs as our Supras? If so, could I potentially find the correct plug off a certain Honda in a junk yard? If it came down to that of course.