Against my better judgement I picked up the ex wifes 2001 Prius after the "mechanic" she took it to ran the HV battery dead. I picked up two Gen II batteries and built me a good battery. Then I cleaned all the corrosion off the harness and terminals and put the HV battery back in. The engine spins but dies. There are no engine codes but under the HV ECU cattegory I get a {P3106 communication malfunction, engine > HV}. I had a spare HV ECU and swapped it and get the same code.Spare engine ECU and the same code also. Not sure where to go from here. Any advice on checking voltages at the ECM ?
Try this, sounds like it could ba a bad engine ECU... let us know.. When using TOYOTA hand-held tester confirm the information code and check it. DTC P3106 - Information code 209, 210, 211 Wiring Diagram Step 1 INSPECTION PROCEDURE CIRCUIT DESCRIPTION Detecting Condition DTC P3106 - Information code 212 INSPECTION PROCEDURE If the information code 212 is output, after confirming the DTC of the ECM, check and repair the applicable DTC. Prior to repairing it, record the DTC of the HV ECU, freeze frame data and history of operation. Then, clear the DTC and check it one more time after starting the system again ("READY" light ON ). CIRCUIT DESCRIPTION Detecting Condition DTC P3106-Information code 394 INSPECTION PROCEDURE If the information code 394 is output, check and repair the ECM power source circuit. If there is no problem in the power source circuit, replace the ECM. Prior to the repair, record the DTC of the HV ECU, freeze frame data and history of operation and clear them. Then, start the system one more time ("READY" light ON ) and check the DTC again.
Interesting. I find the engine ECU on my 2003 Prius is located behind and to the right of the passenger side glove box. This diagram looks more like the location of the ECM (Engine Control Module) of my 2010 Prius. Bob Wilson
that thread did not open properly I don't think. there was more attached to it but it got lost in cyber space??
A couple of postings up is one that has links to images on alldatadiy.com. If you reload this page a few times, you'll notice that, apparently, alldatadiy's preferred way of discouraging deep-linking into their site is that each given URL will be answered with a different image every time. If you reload enough times, you can get to see your Prius's hydraulic transmission control valve, your Prius's fuel damper (whatever a fuel damper is), or whatever. (Hmm, more times than not, I seem to get images having to do with conventional automatic transmissions, CV axles, or brakes.) -Chap
I checked all the obvious problems. I have access to a salvage Prius that I knew had run with no codes. I swapped the battery ecu, then the HV ecu, then the engine ecu with the ignition switch and immobilizer. After all that I still got the same communication error code. I then started pulling plugs on each of the ecms and then doing a scan to see if the scanner could communicate with the engine computer. No dice. My next check bore fruit. I started pulling relays under the hood and then scanning for the ecm. When I pulled the EFI and IGN relays the scanner could communicate with the engine computer. A quick run to the salvage yard for some relays and I had the car running. But it would only run for 3 minutes and then give the triangle of death. A scan revealed igniter circuit fault #1, #2, #3, #4 and P3000 battery control malfunction. I was prepared for the igniter issue since the night the car died I had scanned the car and the only code was a misfire code. I had four coils and ingniters waiting and quickly swapped them out. The car started up and ran smooth, plus the P3000 code did not return. A 30 mile test drive also set no codes. I plan on reinstalling the original ecm back in the car so that the ignition switch key and door keys all match. Now, if I was just getting paid for this job.
I would like to say thanks to everyone on the forum. There are plenty of Gen I Prius's that keep getting pointed my way so I am sure I will be back on here soon.
