P0645 on 2008-2014 Dodge Challenger (SXT, SXT Plus, R/T, R/T Plus, Rallye Redline, Scat Pack, SRT8, SRT8 392) — A/C Clutch Relay Control Circuit
1 vehicles · 1 makes
Most Reported On
P0645 is an OBD-II diagnostic trouble code meaning “A/C Clutch Relay Control Circuit.” A general fault in the A/C compressor clutch relay control circuit driven by the control module. The commanded relay state does not match the measured circuit condition. This code is most commonly reported on 2008-2014 Dodge Challenger (SXT, SXT Plus, R/T, R/T Plus, Rallye Redline, Scat Pack, SRT8, SRT8 392).
Common Causes
Diagnostic Tools
To diagnose P0645, you'll need an OBD-II scanner. Here are our recommendations at every price point.
ANCEL AD310 Classic OBD-II Scanner
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LAUNCH CRP123X OBD-II Scanner
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FAQ
What does P0645 mean?
P0645 stands for "A/C Clutch Relay Control Circuit." A general fault in the A/C compressor clutch relay control circuit driven by the control module. The commanded relay state does not match the measured circuit condition.
What are the most common causes of P0645?
The most common causes of P0645 are: Faulty A/C clutch relay, Open or short in the relay control circuit, Corroded/damaged connectors, Blown fuse, Internal PCM driver fault. The specific cause varies by vehicle.
How much does it cost to fix P0645?
Repair costs vary widely depending on the root cause and vehicle.
Which vehicles are affected by P0645?
Au7o has documented P0645 across 1 vehicle models from 1 manufacturers: Dodge.
Sources (5)
- RecallNHTSA Recall 14V634000 — Dodge Challenger/Charger/300/Durango Alternator May Fail Causing Stall (3.6L, 160A alternator, 2011-2014)
- NHTSANHTSA Owner Complaints — 2013 Dodge Challenger Electrical/Engine Stall While Driving (ODI 11527769, 11219194, 11144130, 11083886, 10959010)
- Forum2013 Dodge Challenger Bad TIPM — 12 Complaints (engine stalls/shuts off while driving, ~$940, ~43,050 mi)
- Forum2009 Dodge Challenger Engine Shuts Down While Driving — 7 Complaints (TIPM/fuel pump, ~$800, ~43,300 mi)
- Forum2013 Dodge Challenger Vehicle Speed Control Problems — 6 NHTSA Complaints (stall/throttle loss, 3 crashes)
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.