P0739 — TCM Engine Speed Output Circuit High

What Does P0739 Mean?

P0739 is a diagnostic trouble code indicating: TCM Engine Speed Output Circuit High. This code relates to the transmission system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

Symptoms of P0739

⚠️ Check Engine Light (MIL) illuminated
⚠️ TCM Engine Speed Output reading stuck at maximum value
⚠️ Related system operating erratically or in default mode
⚠️ Harsh or delayed shifting

Common Causes

🔍 Short to voltage in TCM Engine Speed Output wiring harness
🔍 Corroded or water-damaged TCM Engine Speed Output connector
🔍 Faulty TCM Engine Speed Output outputting maximum voltage
🔍 Damaged wiring rubbing against metal components
🔍 ECM/PCM internal fault (rare)

Frequently Asked Questions

What does P0739 mean?

P0739 indicates: TCM Engine Speed Output Circuit High. The vehicle's computer has detected that the TCM Engine Speed Output is not operating within its expected parameters and stored this diagnostic trouble code.

Can I drive with code P0739?

Only short distances if absolutely necessary. P0739 affects a critical system and should be diagnosed within a few days to avoid further damage.

How much does it cost to fix P0739?

Repair costs for P0739 typically range from $20 to $500, depending on the root cause. Simple wiring or connector repairs are on the lower end, while component replacement costs more. A proper diagnosis ($80–$150 at most shops) will identify the exact cause before committing to expensive parts.

What To Do Next

Possible Fixes

🔧 Inspect and repair TCM Engine Speed Output wiring for short to voltage
🔧 Clean or replace corroded TCM Engine Speed Output connector
🔧 Replace faulty TCM Engine Speed Output

1
Find your vehicle above
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2
Check for recalls
Go to nhtsa.gov/recalls and enter your VIN. Free repairs if covered.
3
Get a professional diagnosis
A code alone doesn't identify the exact failed part. A diagnostic ($50–$150) pinpoints the root cause.

P0739: TCM Engine Speed Output Circuit High