NT-700 Check Engine Light

Can anyone tell me the meaning of the check engine light code--8 flashes? The check engine light came on the motorcycle loss power intermittently for about 60 miles. Then the check engine light went off for about 160 miles and came on again.

Does anyone know the meaning of the check engine light 8 flashes?

Thanks

Handsome Prince

Same thing happened to me, Prince. It was on for about a week but didn't make the bike run any different. I had talked to my dealer's service manager and he told me that as long as it worked OK I wasn't going to hurt the bike. 8 flashes (assuming they're all short flashes) indicates a low-voltage reading at the Throttle Positon Sensor.

After a week or so, the light went off. Then just as I pulled into I-25 rush hour traffic, it came back on and the bike started running really badly. I called the dealer and told them I was going to try to limp in. It was about 15 miles and 55-60 mph was my absolute top speed. I got there, shut it off, and they put a tech on it right away. When he flipped the switch back on, the light was off. But he could tell what the indications had been.

He decided that the voltage rectifier/regulator was the culprit. I think he also replaced the TPS, but I'm not sure about that. Since I can't find the TPS as a separate part on any of the parts fiches, he may not have.

They also replaced the spark plug caps a few weeks later. I haven't had any more trouble.

Good luck!

Phil,

Thanks for your narrative. Part of the confusion, it appears the NT700 does not have a TPS. Instead, it's called, "Motor Assembly" which is found on the throttle body. Since, I and quite a distance from a dealer, I plan to purchase the "Motor Assembly" and have a local shop install it.

Your point related to the rectifier/regulator that this may be the culprit is interesting. Do you know where I might find this part--rectifier, and part number. It's probably a good idea to change both.

Thanks so very much.

Handsome Prince

Don't spend money on that "Motor Assembly" yet. I doubt very much that it is the cause of your problem. It functions to control the idle air circuit and is only in play when the bike is at idle. It's a stepper motor which opens a valve to allow air to flow around the throttle body plates when they're closed.

The bike does have a TPS, but it is part of the throttle body assembly and not available as a separate part. edit: There is a 3 pin blue connector which goes to the TPS. You might want to disconnect and reconnect it. Could be a light contact or funk in there. (Just a suggestion)

Based on Phil's experience, I'd connect a voltmeter to the battery and go for a ride and see what it shows.

Thinking that the motor assembly (part #16430-MEW-921) functioned as the Throttle Position Sensor (TSP). And since, I couldn't identify the TPS in the Honda NT-700 schematic drawings. I brought a motor assembly (MA) (part #16430-MEW-921).

In the process of installing the MA, I noted that the MA in fact is not the TPS and thus does not function in a similar matter.

However, I did discover the the TPS --located just outside the Throttle Assembly, was covered with dust and foreign objects. I blow off the foreign objects and the NT700 has functioned normally for 324 miles.

And so, I assume that the problem with the engine light indicating trouble with the TPS. The problem was dust and a small plant branch interfering the electronic reading within the TPS.

Should you have a similar problem with the engine light indicating a problem with the TPS. Check the throttle body assembly for dust or foreign objects.

Handsome Prince.

Thanks for sharing that with us, Prince. I'm glad your NT is running and hope it keeps it up.

Unfortunately, the problem has returned again --loss of power, check engine light, etc. Does any know what's a TPI stands for?

Now, I am looking at the TPI and rectifier, Regulator (31600-MEW-921) $166.74. Could this be the culpit?

The TPI is the throttle position indicator. It and the rectifier/regulator were replaced when I had the 8-blink PGM-FI indication and the same running issues you've been having. I was still in the first year of my five year warranty so it didn't cost me anything.

I haven't had any more problems.

Handsome Prince said:

Unfortunately, the problem has returned again --loss of power, check engine light, etc. Does any know what's a TPI stands for?

Now, I am looking at the TPI and rectifier, Regulator (31600-MEW-921) $166.74. Could this be the culpit?

Click to expand...

Have you taken a reading on what the DTC is? You can read the DTC relatively easily. You need only to short the DLC terminal and then the MIL (the check engine light) will blink the DTC via long and short blinks. There are 17 DTCs. The DTCs that cover a faulty TP are 8-1 and 8-2 (8 long blinks and 1 or 2 short blinks). 8-1 is for low voltage on the TP circuit while 8-2 is high voltage. This is covered in the service manual on page 6-15.

Phil and Rob,

Thanks for your thoughtful comments. Fortunately, I have a service manual and I appreciate the page reference.

At this point, I have limited time. And so, I will report back on my findings in October.

Another question, where can I find a U.S. Map --to display states that I have visited?

Prince

Phil and Rob,

Thanks for your thoughtful comments. Fortunately, I have a service manual and I appreciate the page reference (6-15).

At this point, I have limited time. And so, I will report back on my findings in October.

Another question, where can I find a U.S. Map --to display states that I have visited?

Prince

Handsome Prince said:

Another question, where can I find a U.S. Map --to display states that I have visited?

Click to expand...

See Here....

Pirate,

Thanks so very much. Map posted.

Prince

Prince,
I am interested if you were able to resolve your engine light issue/performance and how was it solved?

John

Phil,
As you may remember I went through the FI light issues some time ago. I have replaced the Motor Assembly twice and replaced the regulator/rectifier with an aftermarket one, and had decided to replace the battery, the current one being nearly four years old. On leaving the dealer I noticed a burning smell. Further investigation found the plug connecting to the regulator was melted. The wires almost fell out. The plug and wiring replaced the bike ran fine all the way home. The dealer was a bit worried about the heat coming from the regulator so we have decided to fit a new Honda one (They cost just under $500 US here, so I will be ordering one from the US)
Warning to others to check the wiring at the regulator plug. My mechanic said to make sure the wires are pushed on to the terminals with a pair of nose-pliers through the back of the plug. I am hoping this will be the end to the problem.

Thanks for the heads up, axamax! Scary!

http://www.epgsoft.com/VisitedStatesMap/

There's also more instructions:
http://www.nt-owners.org/forums/profile.php?do=editsignature

All,

I had to pay the BIG Bucks --bought a new throttle body $700+. Motorcycle still at dealer the total cost is unknown... I hope to be riding soon. I haven't ridden the NT700 since Sept 2012.

Handsome Prince said:

All,

I had to pay the BIG Bucks --bought a new throttle body $700+. Motorcycle still at dealer the total cost is unknown... I hope to be riding soon. I haven't ridden the NT700 since Sept 2012.

Click to expand...

Please keep us updated. I seriously doubt the problem is the throttle body and I am very interested to hear if replacing it solves your problem.

Was that your only dealer choice? I'm like seagrass, I find it hard to believe that the throttle body could really be your problem.

Whatever, I hope you get your bike and your ability to ride back soon!