Compass Cooling Module Fault Causes Engine Overheating

Had similar control module issues on a 2020 Jeep Renegade. The communication fault turned out to be a failing engine control unit causing incorrect signals to the cooling system. The diagnostic trouble code pointed to a wiring issue initially, but after deeper testing, the data link showed intermittent connection problems between modules. The symptoms matched exactly, engine overheating, coolant loss from pressure buildup, and persistent check engine warnings. The root cause was a corroded connector at the ECU, which disrupted the signal to the cooling fan control. This led to improper fan operation and subsequent overheating. The repair required replacing the damaged connector and reprogramming the control module. This was a serious issue that could have led to engine damage if left unaddressed. The coolant leaks were actually a symptom, not the primary problem. Would recommend getting a second opinion from a shop specializing in electrical diagnostics. These communication faults often get misdiagnosed as simple coolant system problems when the real issue lies in the electronic control systems.

Thanks for sharing that experience. Your case seems very similar to what I went through with my Compass last year. Those CAN bus communication problems can be really tricky to diagnose. My mechanic also found corrupted signals in the software glitch logs before identifying the root cause. Did you remember what the total repair cost ended up being for your control unit fix? Also curious if youve had any related issues pop up since the repair was done?

After getting it properly diagnosed and fixed, the repair cost came to 95 Euro for the faulty cable connection at the control module. The software glitch logs that initially showed communication faults have been completely clear since the repair. The wiring issue turned out to be exactly what was causing the data link problems between modules. The diagnostic trouble codes disappeared immediately after the repair, and the cooling system has been working perfectly for the past six months. No more overheating, no coolant leaks, and the check engine light has stayed off. Really shows how a single connection problem can create cascading issues across multiple systems. Honestly, finding a shop that could properly diagnose the control unit communication error made all the difference. These electronic problems can be frustrating, but once you get the right fix, they tend to stay resolved.

Finally went to a certified dealership after getting tired of the recurring issues. The mechanic there immediately spotted the connectivity issue through their advanced car diagnostics system. Turns out the previous shop missed a critical wiring issue that was causing the control module to malfunction. The fix took about 4 hours and cost 850 Euro, including the new connector and software recalibration. Sure, it was more expensive than the previous attempts, but the problem is completely resolved now. No more coolant leaks, no overheating, and the check engine light has stayed off for the past 3 months. Looking back, I should have gone straight to a specialist shop with proper diagnostic equipment. Sometimes paying more upfront saves money in the long run. The car runs perfectly now, and I havent had a single data link error since the repair.