I got a service engine soon light so I got the code ran at a local shop (for free) It was a p1421 - manufacturer control auxiliary emission controls. They cleared it saying it was probably nothing and if it comes back then to have checked out.

Yes I did a google search but they all showed for BMW cars, not sure if that matters. can anyone verify what this code means? car runs fine so im not too worried.

 

COMPONENT DIAGNOSIS > [VQ37VHR]
P1421 COLD START CONTROL
P1421 COLD START CONTROL
Description INFOID:0000000001734223
ECM controls ignition timing and engine idle speed when engine is started with prewarming up condition.
This control promotes the activation of three way catalyst by heating the catalyst and reduces emissions.
DTC Logic INFOID:0000000001734224
DTC DETECTION LOGIC
NOTE:
• If DTC P1421 is displayed with other DTC, first perform the trouble diagnosis for other DTC.
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting
the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
With CONSULT-III
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Select “DATA MONITOR” mode with CONSULT-III.
4. Check the indication of “COOLAN TEMP/S”.
If it is between 4°C (39°F) and 36°C (97°F), go to the following steps.
If it is below 4°C (39°F), warm engine up to more than 4°C (39°F) and retry from step 1.
If it is above 36°C (97°F), cool engine down to less than 36°C (97°F) and retry from step 1.
5. Start engine and let it idle for 5 minutes.
6. Check 1st trip DTC.
With GST
Follow the procedure “With CONSULT-III” above.
Is 1st trip DTC detected?
YES >> Go to EC-406, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis Procedure INFOID:0000000001734225
1.PERFORM IDLE AIR VOLUME LEARNING
Perform EC-19, "IDLE AIR VOLUME LEARNING : Special Repair Requirement".
Is Idle Air Volume Learning carried out successfully?
YES >> GO TO 2.
NO >> Follow the instruction of Idle Air Volume Learning.
2.CHECK INTAKE SYSTEM
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P1421
Cold start emission reduction
strategy monitoring
ECM does not control ignition timing and engine
idle speed properly when engine is started with
prewarming up condition.
• Lack of intake air volume
• Fuel injection system
• ECM
Revision: 2007 June G37 Coupe
P1421 COLD START CONTROL
EC-407
< COMPONENT DIAGNOSIS > [VQ37VHR]

Check for the cause of intake air volume lacking. Refer to the following.
• Crushed intake air passage
• Intake air passage clogging
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair or replace malfunctioning part
3.CHECK FUEL INJECTION SYSTEM FUNCTION
Perform DTC Confirmation Procedure for DTC P0171, P0174. Refer to EC-232, "DTC Logic".
Is the inspection result normal?
YES >> GO TO 4.
NO >> Go to EC-233, "Diagnosis Procedure" for DTC P0171, P0174.
4.PERFORM DTC CONFIRMATION PROCEDURE
With CONSULT-III
1. Turn ignition switch ON.
2. Select “SELF DIAG RESULTS” mode with CONSULT-III.
3. Touch “ERASE”.
4. Perform DTC Confirmation Procedure.
See EC-406, "DTC Logic".
With GST
1. Turn ignition switch ON.
2. Select Service $04 with GST.
3. Perform DTC Confirmation Procedure.
See EC-406, "DTC Logic".
Is the 1st trip DTC P1421 displayed again?
YES >> GO TO 5.
NO >> INSPECTION END
5.REPLACE ECM
1. Replace ECM.
2. Go to EC-16, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT (ECM) : Special Repair
Requirement".
>> INSPECTION END

 

thanks for all that info!

 

hm am I the only one who ever got this? Anyone know what causes this code?

 

Sadly, I have this problem now too. My part # was 23710-1NC4C. It would really irk me if this light can't be turned off, but at least I don't have that noise anymore *knocks on wood*. Next time I think I'll spend my $40K elsewhere....

 

Tighten your gas cap.

 

this is not a gas cap issue.

 

in case anyone is wondering, there is a fix coming for this soon within a couple months. They are working on a reflash to correct this service light.

 

So is there an actual problem with the engine or is it just a problem with the ecu that is triggering the SES light?

 

apparently it is just a sensor that keeps on tripping. better not be an engine problem!

 

I blame Toyota

 

I hope this is the case.
I've been getting P0456 a few times already and it is suppose to be a very small leak in the evap control system...

 

I have the service light as well. Where did you go to get the code read? Any local autozone?

 

yea autozone or local garage can read the code for you. I would just take it to the dealer, whatever is wrong will be under warranty anyway. 'service engine' lights are emissions stuff

 

Emissions...i see...the thing is i am reluctant to bring my car in for service because it has aftermarket cats, exhaust, hids, suspension, wheels. The light only came on after i installed my hids. Ive driven with the light on for about 1 week on Friday and its still on.