Code result
P2520
A/C Request A Circuit Low
Moderate severity
What it means
The A/C compressor request input A reads stuck low — typically a short to ground or a permanently asserted request. The ECM either sees A/C demanded all the time (cannot release idle-up, raises fuel use) or cannot distinguish a real request from the stuck low level.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Request wire shorted to ground
highOne of the most commonly reported causes for this code — check this first.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Harness chafing through insulation
lowLess common, but worth ruling out after the more likely causes.
Related help
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