P2524 indicates that A/C request input B reads above the level the engine module treats as valid. A line chafed against battery or ignition feed, an open pull-down inside the module or a control unit that latches its output high are the usual explanations. Ford is the one maker found to list it: its 2014 BOSS 302S code list shows P2524 without a lamp mark, just like its A-side counterpart P2521; no thresholds are given. A heavy-duty bulletin from Mack mentions a P252400 on MP10 engines, but in an oil pressure context, so that use is maker-specific and unrelated. CARB A/C monitoring applies only where the request alters fuel or spark control. P2523 is the low side, P2522 the general fault on B. Expect A/C behaving on its own.
Low severity. Can I keep driving?Yes, you can keep driving. The air conditioning may not work.
Symptoms
- Compressor engages although not requested
- A/C cannot be switched off or on as expected
Most likely causes
- Input B wire shorted to battery or ignition voltage
- Sending module output latched high
- Engine module input stage faulty
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: medium
What each character of P2524 means
- P: Powertrain: engine and transmission
- 2: Generic code: same on every make
- 5: Speed and idle
- 24: Specific fault in that system
Frequently asked questions
Can I keep driving with code P2524?
Yes, you can keep driving. The air conditioning may not work.
What causes code P2524?
The most common causes are: input B wire shorted to battery or ignition voltage; sending module output latched high; engine module input stage faulty.
Related codes
Sources
- performanceparts.ford.com: 2014 BOSS 302S OBDII Codes
- law.cornell.edu: 13 CCR 1968.2
- saabwisonline.com: dtc p0645 p0646 or p0647
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.