P1859 Code - Transmission Transfer Case Contact Plate 'D' Open Circuit
Quick Answer
The Transmission Control Module (TCM) monitors the Transmission Transfer Case Contact Plate 'D'. Common causes include Faulty Transfer Case Shift Motor, Transfer Case Shift Motor harness is open or shorted, Transfer Case Shift Motor circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P1859 indicates Transmission Transfer Case Contact Plate 'D' Open Circuit.
- Common causes
- Common causes include Faulty Transfer Case Shift Motor, Transfer Case Shift Motor harness is open or shorted, Transfer Case Shift Motor circuit poor electrical connection.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code P1859 Description
What are the Possible Causes of the DTC P1859?
- Faulty Transfer Case Shift Motor
- Transfer Case Shift Motor harness is open or shorted
- Transfer Case Shift Motor circuit poor electrical connection
How to Fix the DTC P1859?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P1859 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Information for Specific Makes
- P1859 Ford — Transmission Transfer Case Contact Plate 'D' Open Circuit
- P1859 Lincoln — Transmission Transfer Case Contact Plate 'D' Open Circuit
- P1859 Mercury — Transmission Transfer Case Contact Plate 'D' Open Circuit
- P1859 Mitsubishi — Disengagement Too Late With Clutch 1
Frequently Asked Questions about P1859 Code
1. What does OBDII code P1859 mean?
P1859 indicates an open circuit in the transmission transfer case contact plate 'D,' which is responsible for monitoring or controlling transfer case operations.
2. What are the common symptoms of a P1859 code?
Symptoms may include the check engine light or transmission warning light turning on, difficulty shifting between 2WD and 4WD modes, or the transfer case being stuck in one mode.
3. What causes the P1859 code to appear?
Possible causes include damaged or corroded wiring, a faulty transfer case contact plate, a malfunctioning transfer case control module, or loose electrical connections.
4. Can I drive with a P1859 code?
While driving may still be possible, you could experience limited functionality of the 4WD system or risk further damage to the transmission or transfer case.
5. How is the P1859 code diagnosed?
A technician will inspect the wiring and connectors, test the transfer case contact plate and related circuits, and check the transfer case control module for faults.
6. How do I fix a P1859 code?
Repairs may include replacing damaged wiring, repairing corroded connectors, replacing the transfer case contact plate, or reprogramming or replacing the transfer case control module.
7. Can a bad ground cause the P1859 code?
Yes, a poor ground connection can disrupt the electrical circuit and trigger the P1859 code.
8. How much does it cost to fix a P1859 code?
Repair costs vary depending on the issue but can range from $100 for wiring repairs to $1,000 or more for transfer case component replacements.
9. Will clearing the P1859 code solve the problem?
Clearing the code without addressing the underlying issue will likely result in the code returning, as the fault will persist.
10. Can a software update fix the P1859 code?
In some cases, a software update for the transfer case control module may resolve the issue if it’s related to programming errors.
Discuss the causes and fixes for P1859 OBDII Code
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