User:Snewkirk7953/ENES-100/project 1

Week0 Preferences
This week I was assigned to a team exploring ECUs, or Electronic Control Units. These are commonly used in motor vehicles to control electronic subsystems such as door locks, transmissions, and brake systems. This weekend I found three interesting videos on the practical uses of ECU tuning:
 * ECU tuning with computer software
 * ECU reflash for improving motorcycle performance
 * How tuning ECU for ignition timing increases horsepower

Week1 Narrative
My team now has the ECU out of a 1996 Isuzu Hombre, so the next step is to remove the unnecessary parts from the mass of wires. There are three ports on the ECU that are color coded with bundles of wires (green, blue, and white). The wire bundles are intertwined with one another and an external A/C plug, which isn't needed, so I unplugged the wires connecting to it and sorted all those wires back into the three bundles. There was also a red wire and black wire for power that were connected only to the A/C plug, so those wires are now loose with the rest of the team's equipment to be used later (to power the ECU).

Once the wires were in three neat bundles, I plugged them back into the ECU to keep them organized. There is a connector for the ODB code reader that was taken from under the truck's steering wheel that needs to be reconnected to the ECU in order to read it. The ODB connector has six wires in various colors attached, and the wires they connect to are somewhere among the mass of wires connected to the ECU. After removing all of the electrical tape wrapped around the wires and sorting through them, and I was able to find all of the possible matches and separate them out. Next week I will try to determine which of those wires are the correct ones.

Week2 Narrative
My job this week is to make a list of open source ECU's and open source car simulation mechanisms, cost, features, and incompatibilities, and determine how standardized the ECU market is.

I spent a couple of hours searching for open source ECU simulation software and reading the reports of companies from various countries on the ECU market and industry standards. I created a wiki page with my findings.

Week3 Narrative
Status of the Finish objectives at the beginning of this week:
 * [ ] Get ECU outside the car powered on and talking to an ODB code reading device
 * [x] Make list of open source ECU's and open source car simulation mechanisms, cost, features, incompatibilities. Determine how standardized the ECU Market is.
 * [ ] Document wiring harness of an ECU by figuring out the resistance between every possible combination of two wires in the same cable bundle.

This week's task is to work on the last objective by first supplying power to the ECU.

After my classes on Monday 9/30, I identified which of the ECU plugs were A, B, and C according to a diagram and determined the functions of some of the wires and plug pins: According to the colors of the wires on the ODB connector, the 11 possible wire matches from the three plugs are A13, A14, A16, A30, B1, B3, B10, B12, B14, B23, and C17. However, after comparing these with the wiring diagram, I found that A14, B1, B23, and C17 are not shown on it.
 * Plug A is black, and has 20 active pins (out of 32)
 * Plug B is white, and has 18 active pins (out of 32)
 * Plug C is blue, and has 16 active pins (out of 32)

Now that I know that the diagram and actual plugs do not correspond exactly, I had to go over the diagram to find out if any other wires were missing. There are 54 wires in the bundles, and 49 shown on the diagram. I originally assumed there were five wires missing, so only one more needed to be identified. After going through all the wires, I found that there were actually nine missing wires (A5, A14, A23, B1, B23, B30, B32, C2, and C17) because four of the wires on the diagram were actually doubled, and apparently feed into two separate locations (B3, B17, C31, and C32).

Next, I found which of the pins on the ECU are ground. I used a multimeter to locate 9 (A17, A25, B23, B1, B12, B14, C17, C7, C9). These returned about 3 ohms of resistance. In the process, I also discovered 7 pins that returned between 500 and 2000 ohms (B18, B19, B31, C27, C29, C31, C32). I do not yet know what these are.

The next step is to continue searching for the wires that provide power to the ECU.

When I searched for additional wiring diagrams online for the location of the power input, I found nothing useful aside from the diagrams I already had. It appears that very little documentation on a 1996 Isuzu Hombre ECU exists, if at all.

I also discovered that the pins on the ribbon cables that connect the two ECU boards have some ground pins among them.

Unfortunately, locating the power input to the ECU is harder than I expected, and I still have yet to find it. Once the power pins are known, the next step is to buy an ECU simulator to trick the ODB device into reading it as if the ECU was still in the car.

Week4 Narrative
After connecting the ECU and OBD connector (with power supplied- positive to orange wire, and negative to black wire) to a USB port, the computer recognized the device input and a blue LED lit up on the USB converter. I looked in the device manager and the computer does not seem to be able to identify the ECU, though.

Next, I used the program Putty.exe to test the device's communication with the computer. Unfortunately, Putty.exe did not read a response.

The next step is to buy a Can Bus from Amazon to act as a simulator.

Looking at the wiring diagram, I determined that the three pink wires (one from each plug) were possible power lines. I repeated the setup from above, this time bundling all the wires of the same color coming from the plugs, to each matching wire on the OBD connector, so that the three black wires were all connected to the OBD. After supplying positive power to the orange wire and negative power to the black wires, I touched the pink wires to the orange line to see if power would go to the ECU. The power to the code reader died, but I was able to fix it by increasing the current allowed (since one of the pink wires carried a lot of current).

Unfortunately, the code reader still gave a connection error. I would like to try more wire combinations, but for now it seems that the Can Bus is the best option to try next.