P0695
Fan 3 Control Circuit Low
Powertrain Engine Cooling Cooling fan control circuit 🟡 Moderate — Fix within a week
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What This Actually Means
In plain language — no jargon

The engine cooling fan's control circuit is receiving a low voltage signal, meaning the ECU can't properly command the fan to run. It's like trying to turn on a light switch but the electrical signal is too weak to flip it.

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Symptoms You May Notice
3 known symptoms for this code
Engine overheating or running hotter than normal
Fan does not engage or runs intermittently
Check engine light illuminated
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Embedded Systems Insight
What the ECU/ECM is actually computing

The ECU monitors the voltage output on the Fan 3 control circuit, which should toggle between battery voltage (high) when the fan is commanded on and near ground (low) when off. A persistent low-voltage condition indicates the ECU cannot establish proper control of the fan relay or motor.

Voltage & Parameter Thresholds

Parameter Normal Range Fault Condition
Fan 3 Control Voltage 0V (off) or 12V (on) Below 0.5V when fan should be on
Circuit Resistance <5 ohms wiring path >10 ohms indicating loose connection
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Diagnostic & DIY Fix Guide
Check these in order — from cheapest to most complex
1
Battery terminals and ground straps
Clean corrosion from battery posts and engine ground connections to restore proper voltage.
2
Fan control relay
Inspect relay socket for burnt contacts and swap relay to test or replace if damaged.
3
Fan motor wiring harness
Check for broken wires, corrosion, or loose connectors in the fan circuit using a multimeter.