Nissan Frontier DTC P1564:  ASCD Switch Malfunction

P1564 Nissan Frontier

P1564 is a common code that can occur in the Nissan Frontier.  It indicates that the ECM has detected an issue with the Automatic Speed Control Device (ASCD) More specifically, with the voltage resistance at the switch itself.

ASCD is just Nissan’s overly complicated way of saying cruise control.  It should not be considered a breakdown risk (but the cruise control will be inoperative).

You can see the switch.  It’s just your cruise control buttons and assembly.  You’ll still need to pull the airbag/steering assembly to test it.

Nissan Frontier P1564 Symptoms

Nissan Frontier P1564 Diagnosis

P1564 does not have many symptoms other than the check engine light being illuminated (probably why you are here), and the cruise control system not working.  Other than that, your Frontier should keep running and driving fine.

Causes + Fix

P1564 in the Nissan Frontier is almost certainly going to be caused by an issue with the ASCD steering switch.  

ASCD Switch (Most Common Fix)

The ASCD switch is the many buttons on your steering wheel that lets you operate the cruise control.  As you push them, different voltage levels are being sent to your Frontier’s ECM.  This signal tells the cruise control to engage, reduce speed, increase speed or quit.  

When the wrong voltage is detected, the ECM will disable the cruise control and throw P1564.

More than likely, the switch itself will need replaced, but you should do your due diligence by testing the wiring harness going to the steering wheel first.  You’ll need a multimeter to test the switch itself.  Here’s a great video of a gentleman diagnosing P1564.  It ends up being the switch itself in this case.  It’s very informative.

There are three pain points where the voltage should be tested:

  • Between the spring switch and the ECM
  • Between the ASCD switch and the steering wheel harness (requires removing airbag assembly, if you don’t know what you’re doing it can activate and pop you).
  • At the ASCD switch itself.  Check the incoming voltage and outgoing voltage.  Check that linked video a few lines up.  It’s very thorough.

ECM (Not Very Likely) 

If everything checks out with the wiring harness and ASCD switch, it could be the ECM that is at fault.  But, it’s so unlikely that you should double check everything first.

Nissan Frontier P1564 Conclusion

P1564 is usually caused by a bad ASCD switch.  We recommend taking your Frontier to a shop if you aren’t comfortable with taking the steering assembly apart.