Powertrain
generic / SAE
P2520
A/C Request A Circuit Low
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.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number5 / 20
Possible causes
- Request wire shorted to ground high
- Connector pins corroded - high contact resistance low
- Harness chafing through insulation low
Inspection / repair
- Difficulty: medium
- DIY: shop recommended
- Estimated cost: 80–500 €
- Estimated time: 0.4–2 h
- Component: ac request input a
- MIL / check engine light
Sources
References
sae:J2012