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P0804

P0804: Transmission Control Module (TCM) Range/Performance Problem

Fix Cost
$200 - $1000
Parts & Labor
Difficulty
3/5
Moderate
1-2 hours
DIY Possible?
❌ No
Pro recommended
Category
Powertrain
System

📖 What Does P0804 Mean?

The TCM has detected a problem with the transmission's range and performance, which can cause issues with gear shifting, hesitation, or slipping.
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Symptoms

  • Transmission hesitation
  • slipping
  • or difficulty shifting gears
  • unusual noises
  • or the transmission warning light on the dashboard.
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Common Causes

  • Faulty transmission solenoid
  • faulty transmission sensor
  • low transmission fluid level
  • clogged transmission filter
  • or a faulty transmission control module.
Fix Guide
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Possible Solutions

1. Check transmission fluid level and top off if necessary. 2. Scan for any other trouble codes. 3. Check transmission solenoid and sensor for any signs of damage or corrosion. 4. Replace faulty transmission solenoid or sensor. 5. Replace transmission filter if clogged. 6. Re-program the TCM if necessary.

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Common Questions About P0804

Q

Can I drive with code P0804?

A

You can drive for a short time, but should address code P0804 soon to avoid worsening the problem or failing an emissions test.

Q

How much does it cost to fix P0804?

A

The estimated repair cost for code P0804 is between $200 and $1000. This includes parts and labor for most makes and models.

Q

Is this code easy to fix myself?

A

This repair is considered moderate. It may require specialized tools or significant disassembly. Professional help is recommended if you aren't an experienced DIYer.

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Complex codes like P0804 can be tricky. Don't risk it if you're unsure.

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Related Diagnostic Codes

Other codes that may appear with P0804

💡 Why These Codes Are Related:

  • Similar Issues: Same root cause or component failure
  • Related Problems: Often occur together due to system interactions
  • Sequential Codes: Progressive failure stages or multiple sensors
  • Same System: Components within the same automotive system