[How To] Read & Reset MIL

Joined
Jun 5, 2011
Messages
349
Location
Western Washington
Bike
2010 NT700V, 2015 CB500X
Read & Reset Maintenance Indicating Light (MIL), aka Check Engine Light (CEL)

Before STARTING the NT, verify the MIL light has cleared after the short self-check. If the MIL stays on after the short self check, don't start the NT or cycle the ignition switch to clear the MIL.

If the MIL is present after the short self-check before starting the engine, read the MIL code by:
-shifting to neutral
-release clutch
-lower kickstand
Read MIL flashes. Long is ~1.3 seconds & counts as 10. Short is .5 second & counts as 1. If there is more than one code, it should blink one code then the next in numerical order (not chronological order), then it continues to repeat flashing the codes.

If the MIL clears as normal after the self check, but the NT is hard to start & no MIL as come on, crank to start for >10 seconds & a MIL should come on. Then while the MIL is on, do the above to read the MIL flash codes.

If you notice a MIL when riding, pull over and don't turn engine off. If the engine dies because of the MIL, don't turn the ignition off. Read the MIL flash codes by performing the following steps.
-shifting to neutral
-release clutch
-lower kickstand
Read MIL flashes. Long is ~1.3 seconds & counts as 10. Short is .5 second & counts as 1. If there is more than one code, it should blink one code then the next in numerical order (not chronological order), then it continues to repeat flashing the codes.

How to read MIL codes stored in ECM.
If you see a MIL, the code for MIL will also be stored in your ECM even if the MIL has since cleared. If you want to read the fault for a previous event when the MIL was on but it has since cleared, do this:
-Ignition switch off
-Remove seat and left side cover.
-Remove the red cap off of the Dummy Load Connector (DLC). It's the 4 wire connector with the red cap just forward of the ECM (main computer card).
-Insert a shorting wire into the Brown and Green wire's terminals of the DLC. I use a ~4" long speaker wire. Any small wire should work. Don't jam a big wire in there.
-Verify engine kill switch is ON.
-Turn Ignition switch ON
-Read blink codes on MIL
If there is more than one code, it should blink one code then the next in numerical order (not chronological order), then it continues to repeat flashing the codes.
-Turn ignition switch off, remove shorting wire, replace cap & side cover & seat.

How to clear the codes in the ECM.
The ECM doesn't save the previous fault codes in chronological order. Because of that, it is a good idea to clear the codes & keep the register empty so that in an event of a new MIL fault code occurring there won't be other codes stored in the ECM to confuse any future troubleshooting. If you are concerned about having proof of past codes (ie ...to show a shop) I would suggest videoing your old codes flashing. To clear the codes:
-Ignition switch off
-Remove seat and left side cover.
-Remove the red cap off of the Dummy Load Connector (DLC). It's the 4 wire connector with the red cap just forward of the ECM (main computer card).
-Insert a shorting wire into the Brown and Green wire's terminals of the DLC. I use a ~4" long speaker wire. Any small wire should work.
-Verify engine kill switch is ON.
-Turn Ignition switch to ON.
-Temporarily remove the shorting wire in the DLC plug. The MIL will have a solid yellow light for 5 seconds, reinsert the shorting wire into same Brown/Green wire terminals on the DLC during the 5 seconds.
-Verify MIL goes OFF, then starts blinking. The ECM memory is now cleared. If you're unsure that the codes were cleared try reading the stored codes in the ECM from steps above.
-Turn ignition switch off, remove shorting wire, replace cap & side cover & seat.

MIL blink codes for the NT
1 MAP (Manifold Air Pressure) Sensor Voltage high or low
2 MAP Sensor performance problem
7 ECT (Engine Coolant Temperature) Sensor voltage high or low
8 TP (Throttle Position) Sensor voltage high or low
9 IAT (Inlet Air Temperature) Sensor voltage high or low
11 VS (Vehicle Speed) sensor lost
12 #1 injector malfunction. Will not start.
13 #2 injector malfunction. Will not start.
18 CMP (Cam Position) sensor lost. Will not start.
19 CKP (Crank Position) sensor lost. Will not start.
21 O2 sensor malfunction
23 O2 sensor heater malfunction
29 IACV (Idle Air Control Valve) malfunction
 
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Sorry for the long post. It is a cut-n-paste of previous post that was buried and difficult to find. So to make it more upfront & available in a "How To"...here it is.

Good news. No service manual or special tools needed ...just a cell phone, tablet, laptop. One less reason to pack a service manual "just in case."
 
Thank you Dan, I'm going check(if still there) and the clear code 19(if still there) from the ECM after I had replaced the CKP sensor over the early fall season. Thanks for the info I'm going to keep this(paper copy shrunk) and small piece of wire in the owners manual for any future issues.
 
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Super!! My MIL light just stayed on yesterday during a ride home!!
Thanks for posting!
 
On start-up this morning, I noticed the engine light flashing, but did not note the specific code. I did notice it was short-flashing a number of times, so it's in the 7,8,9 range. Had turned off the bike to take a look in the service manual, but upon turning the ignition back on, it had reset and the code is now in storage. Rode the bike to work, noting that throttle position - when not accelerating - seemed to be cutting out as if I'd cut the throttle completely, acting more likes an on/off toggle instead. I shall follow the above sequence to determine the correct code and go from there. Wish me luck!
 
Hi dnktg...

Just wanted to revive this thread as possibly needs correcting?....
The Haynes manual, pg 4.13 lists fault codes, in agreement with the list above, except it does not have a fault code 22, but has fault code 23 with the same symptoms + causes re o2 sensor heating element.
In addition it lists ..
29.... Engine stalls/ hard to start/ rough idle.... Faulty idle speed control valve.
32 ....Engine runs normally .....Faulty ECM EEPROM

Perhaps the fault code differences + additions are specific to USA and Euro Deauvilles?
 
Ah...that 29 is already listed !
So code 23 , not 22?
And a 32.

Is it possible to edit your posts once sent on this site?
Also finding when I select reply, it seems to be with previous msg quoted by default, (which I deleted) yet there is a separate button for including quote if desired!
 
Sorry for the long post. It is a cut-n-paste of previous post that was buried and difficult to find. So to make it more upfront & available in a "How To"...here it is.

Good news. No service manual or special tools needed ...just a cell phone, tablet, laptop. One less reason to pack a service manual "just in case."
Thanks Dan, I forgot to clear the codes when my NT lost its crank position sensor 2 years ago. Will try this tomarrow.
 
Perhaps the fault code differences + additions are specific to USA and Euro Deauvilles?

Very possible... The US version was stripped down a bit. We don't have HISS so any codes involving it may not apply here.
 
Ah...that 29 is already listed !
So code 23 , not 22?
And a 32.

Is it possible to edit your posts once sent on this site?
Also finding when I select reply, it seems to be with previous msg quoted by default, (which I deleted) yet there is a separate button for including quote if desired!
Ah, right you are. I was able edit the 22 to a 23.
I made the list from the Honda Shop Manual and it doesn't list a 32. Don't recall ever hearing of someone experiencing a code 32, or a 22/23 for that matter.
 
My fault codes seem to have been stored neither numerically nor chronologically!

They flashed out in this sequence...
1, 2, 8, 9, 23, 29, 19, 12, 13.

I say they are not chronological, as I am sure 23 was the last up, when I did a test with the O2 sensor out. 2 weeks before that I had the 12 when I forgot to reconnect an injector on reassembly.
I'll look at the other injector connector but don't think it's a problem ( 13).
The 1 + 2 are probably re a hole in the vacuum hose, which has been renewed now, but I'll do some basic checks on the Map sensor.
I'm worried about the 8, 9, and 19 which need investigating, especially 8!
I've posted more detail on uk site, but just wanted to point out that my list seems numerical up to code 29, but then is followed by 19, 12, 13, and that 23 was the last code I saw, so I doubt it is even a chronological sequence! Very strange then .
 
Ah, right you are. I was able edit the 22 to a 23.
I made the list from the Honda Shop Manual and it doesn't list a 32. Don't recall ever hearing of someone experiencing a code 32, or a 22/23 for that matter.
OK, ran my tests. First, there is an error in the procedure. For reading and clearing codes, the phrase "Verify engine kill switch" is "on" is wrong and non sensical to boot. It is the "Engine Run Switch", or at least that is what my 15th production model of 2010 says, and it needs to be in the "Run" position. I tried this twice and at least that is how MY bike works.
I got 2 codes stored. The first was 23, which means O2 sensor heater and I have no idea what that even is but at one time I fought taking off the sensor connector and the exaust and perhaps I ran the bike to see what it sounded like. I cant remember. The second is the 19 code when my crank position sensor became intermittant and I had to replace it.

I then cleared the codes.

An interesting aside is that, like my old 1996 Subaru, and probably all engines with computers, there is a cam position sensor and a crank position sensor. The computer has to know each to know when to fire the plugs and injectors. But consider this. The little guy in the computer only needs to see both inputs ONCE and since there is a relationship between them (as the cam spins half the speed of the crank), once he knows where one is in relation to the other, (cam and crank) he only needs one operational after the engine starts to run the engine. This is called "historical memory" . This is important as these sensors in the 1996 Subaru fail as a matter of course and become intermittant.. They are nothing more than potted coils of wire so fine they break internally and make and break with heat. I finally learned to use a can of freeze mist to isolate the bad sensor on my Sub. and my NT "fixed" itself as Frosty and I were on the side of the road in Spokane ready to try and go to Spearfish. If YOU experience an NT that doesnt start after becomeing hot like I did, and the bike then starts after it is cool, you can in all likelyhood ride home without stopping the engine due to this historical memory business, just like I did (to pick up the FJR) and like I did with my 1996 Subaru.
 
On start-up this morning, I noticed the engine light flashing, but did not note the specific code. I did notice it was short-flashing a number of times, so it's in the 7,8,9 range. Had turned off the bike to take a look in the service manual, but upon turning the ignition back on, it had reset and the code is now in storage. Rode the bike to work, noting that throttle position - when not accelerating - seemed to be cutting out as if I'd cut the throttle completely, acting more likes an on/off toggle instead. I shall follow the above sequence to determine the correct code and go from there. Wish me luck!
hey that’s exactly the problem i’m having, and my light is blinking code 8. how did you solve your problem? note message below, do you know what he meant?
 
I think he said that because the throttle body includes the sensor. $$
That doesn't mean that is the problem. Could still be bad connection, battery issue, other charging system issue.

Brad
 
What Brad (ARKNT) said. Although it seems to me that someone found an automotive TPI that could be used to get around having to replace the whole throttle body.
 
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