P0218
CriticalTransmission Fluid Over Temperature
Transmission System
P0218 — Instant Answer
Transmission Fluid Over Temperature
Severity: CRITICAL
Meaning: Transmission fluid temperature is too high. Overheated transmission fluid breaks down and loses its lubricating properties.
Safe to drive? NO if CEL is flashing. YES with caution if solid, but repair this week.
Estimated repair cost: $50 - $300
Most common causes:
- 1. Towing or heavy load in hot weather (35-45% of cases)
- 2. Low transmission fluid (35-45% of cases)
- 3. Clogged transmission cooler (10-25% of cases)
- 4. Failing torque converter (10-25% of cases)
Symptoms
- ⚠️Transmission slipping
- ⚠️Burnt fluid smell
- ⚠️Harsh shifting
- ⚠️Transmission warning light
Related Symptoms
Common Causes
How to Diagnose P0218
- 1Stop towing and let transmission cool
- 2Check transmission fluid level and condition
- 3Inspect transmission cooler lines
- 4Check if auxiliary cooler is needed
OEM Procedures for P0218
P0218 affects the Engine Control Module. Found 146 OEM service manual procedures.
12 90 120 Removing and installing/replacing control unit bracket (Cooper 4-door hatchback, Cooper 2-door hatchback, 2020-2023) - Replacement: Remount DME control unit and the integrated supply module (PDM)
12 90 120 Removing and installing/replacing control unit bracket (Cooper 4-door hatchback, Cooper 2-door hatchback, 2020-2023) - Replacement: Remount DME control unit and the integrated supply module (PDM)
12 90 120 Removing and installing/replacing control unit bracket (Cooper 4-door hatchback, Cooper 2-door hatchback, 2020-2023) - Replacement: Remount DME control unit and the integrated supply module (PDM)
12 90 120 Removing and installing/replacing control unit bracket (Cooper 4-door hatchback, Cooper 2-door hatchback, 2020-2023) - Replacement: Remount DME control unit and the integrated supply module (PDM)
12 90 120 Removing and installing/replacing control unit bracket (Cooper 4-door hatchback, Cooper 2-door hatchback, 2020-2023) - Replacement: Remount DME control unit and the integrated supply module (PDM)
12 90 120 Removing and installing/replacing control unit bracket (Cooper 4-door hatchback, Cooper 2-door hatchback, 2020-2023) - Replacement: Remount DME control unit and the integrated supply module (PDM)
12 90 120 Removing and installing/replacing control unit bracket (Cooper 4-door hatchback, Cooper 2-door hatchback, 2020-2023) - Replacement: Remount DME control unit and the integrated supply module (PDM)
12 90 120 Removing and installing/replacing control unit bracket (Cooper 4-door hatchback, Cooper 2-door hatchback, 2020-2023) - Replacement: Remount DME control unit and the integrated supply module (PDM)
Showing 8 of 146 procedures
OEM Diagnostic Flowchart
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Related Resources
Repair guides, symptom pages, and wiring diagrams related to P0218.
Exact Repair Workflows
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Open the exact repair flow most commonly associated with P0218 on this vehicle.
Open the exact repair flow most commonly associated with P0218 on this vehicle.
Open the exact repair flow most commonly associated with P0218 on this vehicle.
Open the exact repair flow most commonly associated with P0218 on this vehicle.
Related Symptoms
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Open the exact vehicle hub for a repair workflow commonly associated with P0218.
Open the exact vehicle hub for a repair workflow commonly associated with P0218.
Open the exact vehicle hub for a repair workflow commonly associated with P0218.
Related Codes
The TCM (Transmission Control Module) has detected a fault and sent a message to the ECM. This is a general indicator that transmission-specific codes are stored.
Fault in the torque converter clutch (TCC) solenoid circuit.
The engine coolant temperature has exceeded the safe limit. This is an overheating condition that can cause severe engine damage.
Frequently Asked Questions
- Can overheated transmission fluid damage the transmission?
- Yes — every 20°F above normal cuts fluid life in half. Severely overheated fluid breaks down and causes internal damage.
- How hot is too hot for transmission fluid?
- Most transmissions are designed for 175-200°F. Above 240°F, fluid begins to break down rapidly.
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Author & Review
Written by AllOEMManuals Editorial Team. Reviewed by ASE-certified technicians and updated with factory-reference checks for fitment-sensitive steps.
This guide was drafted with AI assistance and reviewed for accuracy by a human editor.
Last updated: 2026-05-07