| Author | Message | ||
     Mmcn49 |
Here’s what I did: Installed two WB sensors & controllers. Powered them with a fuse tap on the ignition relay side of the 15 Amp ignition fuse. There is about a 3 to 4 Amp current draw for the WB heaters and controllers. I protected the sensors & controllers with a 10 Amp fuse. The rest of the electrical system is unchanged. Here’s what happened when I went to start the engine last week: Check engine light came on then went off. The exhaust valve actuator motor cycled open then closed The starter cranked for 2 or 3 seconds then stopped. Turned the ignition off then tried again. Check engine light came on then went off. The exhaust valve actuator motor cycled open then closed. Starter cranked for 1 second then everything went dead. Troubleshooting showed that one of the relays died. Replaced relay and tried again. When key is turned on, the key switch relay is the only one that clicks. The Check Engine light DOES NOT come on. The exhaust valve actuator motor DOES NOT cycle. With the key on there is 12 volts on the Orange wire going to the actuator motor. When the key is first turned on there is 1.8 volts on the Tan/Violet Hall Effect sensor wire from the ECM to the motor. It drops to 0.7 volts after 3 or 4 seconds. There is 0 volts on the White control signal wire from the ECM. Verified that all fuses and relays are good. As far as I can tell nothing is smoked. Have made a few other tests, but would like some input before going further. I’m concerned that I don’t have a control signal coming from the ECM, however I do have either a power or signal voltage coming from the ECM for the Hall Effect sensor in the actuator. Could the ECM be partially smoked. Any suggestions on where to go next? | ||
| Iamarchangel |
Umm, go back to the bit where the starter cranked for a second then everything went dead. You haven't mentioned if you checked the battery as in load tested it. No point checking anything else until that has been done. | ||
| Mmcn49 |
Checked that. It started my 72 Beemer. Also verified power to the ECM across pins 1 & 2 on Black Connector 10. Verified voltage on the Red wire at the ECM fuse. When I plugged the fuse back in, the check engine light came on for about 1 second and the exhaust valve actuator motor cycled, but it still doesn't start. The other side of the fuse goes to pin 5, (keep alive wire) on the ECM Gray Connector 11. Where do I go next? Is there a way to test the ECM? | ||
| Mmcn49 |
Also, I've disconnected the new WB sensors and LC-1's. | ||
| Iamarchangel |
The manual is pretty hardline here, according to the tests you've done, the ECM is toast. There's something still kicking in there so I would undo everything I had done and restore to original. The ECM is very sensitive to ground faults. Check for that. Where is that 10 amp fuse for the sensors and controllers? Also, and this is my limitation on the ECM system, check to make sure current flow is the right direction. There's something about sensors ground to the ECM. Not sure how it works but it is opposite to what is expected. You may have accidently grounded the ECM through the sensors. Also, this came up on a recent post, somebody had put new electricals in and thought they were grounded. However, he had attached the grounds to a painted piece so it wasn't actually grounded. | ||
| Mmcn49 |
Found the problem. It’s in the fuse block. Voltage is not reaching the start switch from the key switch fuse, in the fuse block. When I bypassed the fuse, the bike started instantly. Now I have to get into the wiring rats nest under the fuse block and find out what’s wrong. This is somewhat frustrating. With all the work that was done, I never touched the key switch fuse. Mike thanks for responding. It helps getting input and feedback from others. | ||
| Iamarchangel |
Hey, you're welcome, I figured that something else besides a dead ECM was up from your info. Seems to me that Buells have a lot of sharp bends and wear points for thinly insulated wire. I've found a couple of worn places on mine and read about more here from others. I'd be tracking those wires and tape over any wear spot. Once you find the right one, you could probably go back to where you were. You probably moved a wire from where it was comfortable to where it caused a problem. |
