My ’96 RS with 104K has an electrical problem - I think it's an electrical problem - and I’m stumped in diagnosing it.
Earlier in the spring, the motor occasionally cut out when warm, but immediately restarted. Finally, it began exhibiting the classic HES wiring symptom: it would only restart after cooling off. I removed the HES plate, and replaced the sensors and wiring as Dana Hager describes. The plate-and-harness combo worked fine on the bench. I removed and inspected the HT coil and wiring, and found no cracks or other suggestions of problems. Reinstalled, the bike started right up and ran well.
I’ve been riding it to work again for several weeks. After a week, it cut out on the way to work one morning, only a few blocks from home. It restarted immediately, and didn’t quit again. Thinking about the job (“Look where you last worked”) I realized I hadn’t done a good job on the connectors. Last weekend I pulled the tank, did a thorough Deoxit job on the HES wiring harness plug-and-connector, the fuel tank wiring plug-and-connector, the two FI injector connectors, and removed and reinstalled the main CPU plug as well a few times for good measure.
Monday and Tuesday, it ran fine. This morning, the bike quit again just after leaving home. It restarted immediately, then quit again a block later. Again, it restarted immediately, and didn’t falter coming home at the end of the day.
During all three morning quits, the RID stayed on; I conclude the problem isn’t in the sidestand switch, kill switch, or their wiring. Because it was still in gear and fired right up when I squeezed the clutch and hit the starter button, I think the clutch perch switch and wiring are OK. The alternator light came on when the bike stopped running, and the bike restarted without jiggling the key or turning the ignition off and on, so I think the problem isn’t the main power feed in the ignition switch. The battery is a near-new (<4 months in use) Odyssey, and the bike always cranks briskly.
If the problem were the common wiring harness fault (too tightly Zip-tied to the frame), you’d think sometimes the motor would quit at other times, or in response to handlebar movement, or wouldn’t always restart immediately. But it doesn’t. it always starts immediately, runs well, and shows no symptoms other than these three (so far) cold-engine quits.
As I mentioned, after rebuilding the HES tested good, and 99% of the time it operates correctly.
Still, as far as I can see the quits are only consistent with a second but different HES fault.
Any ideas what it might be? Any ideas how to move further with diagnosis?
Earlier in the spring, the motor occasionally cut out when warm, but immediately restarted. Finally, it began exhibiting the classic HES wiring symptom: it would only restart after cooling off. I removed the HES plate, and replaced the sensors and wiring as Dana Hager describes. The plate-and-harness combo worked fine on the bench. I removed and inspected the HT coil and wiring, and found no cracks or other suggestions of problems. Reinstalled, the bike started right up and ran well.
I’ve been riding it to work again for several weeks. After a week, it cut out on the way to work one morning, only a few blocks from home. It restarted immediately, and didn’t quit again. Thinking about the job (“Look where you last worked”) I realized I hadn’t done a good job on the connectors. Last weekend I pulled the tank, did a thorough Deoxit job on the HES wiring harness plug-and-connector, the fuel tank wiring plug-and-connector, the two FI injector connectors, and removed and reinstalled the main CPU plug as well a few times for good measure.
Monday and Tuesday, it ran fine. This morning, the bike quit again just after leaving home. It restarted immediately, then quit again a block later. Again, it restarted immediately, and didn’t falter coming home at the end of the day.
During all three morning quits, the RID stayed on; I conclude the problem isn’t in the sidestand switch, kill switch, or their wiring. Because it was still in gear and fired right up when I squeezed the clutch and hit the starter button, I think the clutch perch switch and wiring are OK. The alternator light came on when the bike stopped running, and the bike restarted without jiggling the key or turning the ignition off and on, so I think the problem isn’t the main power feed in the ignition switch. The battery is a near-new (<4 months in use) Odyssey, and the bike always cranks briskly.
If the problem were the common wiring harness fault (too tightly Zip-tied to the frame), you’d think sometimes the motor would quit at other times, or in response to handlebar movement, or wouldn’t always restart immediately. But it doesn’t. it always starts immediately, runs well, and shows no symptoms other than these three (so far) cold-engine quits.
As I mentioned, after rebuilding the HES tested good, and 99% of the time it operates correctly.
Still, as far as I can see the quits are only consistent with a second but different HES fault.
Any ideas what it might be? Any ideas how to move further with diagnosis?
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