Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This means that the car's computer is having trouble talking to the part that controls the gears. It's like when you can't hear your friend on the phone because of a bad connection.
The P1698 code indicates a communication problem between the Transmission Control Module (TCM) and the Powertrain Control Module (PCM).
The P1698 code is triggered when the PCM detects a loss of communication with the TCM. This can be due to wiring issues, a faulty TCM, or problems with the PCM itself. The TCM is responsible for controlling the transmission, and any communication failure can lead to improper transmission operation.
• Check Engine Light is on
• Transmission may not shift properly
• Vehicle may go into 'limp' mode
• Faulty Transmission Control Module (TCM)
• Wiring issues or poor connections
• Faulty Powertrain Control Module (PCM)
TCM: Transmission Control Module
PCM: Powertrain Control Module
• Check for other diagnostic trouble codes (DTCs) that may indicate a related problem.
• Inspect the wiring and connectors between the PCM and TCM for damage or corrosion.
• Test the TCM and PCM for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the faulty TCM if necessary.
• Replace the PCM if it is determined to be faulty.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $1000
Moderate
• Dodge Grand Caravan
• Jeep Grand Cherokee
• Chrysler Town & Country
• Regularly inspect and maintain vehicle wiring and connectors.
• Ensure all software updates for the vehicle's computer systems are applied.
• Avoid exposure of electronic components to moisture.
Communication Error
• Do not ignore the Check Engine Light; have the vehicle inspected promptly.
• If the vehicle is in limp mode, drive carefully and avoid high speeds.
• Consult a professional mechanic for accurate diagnosis and repair.
Check with the vehicle manufacturer for warranty coverage on electronic components.
The P1698 code has been reported in vehicles with electronic transmission control systems, particularly in older models with known wiring issues.
Moderate – While the vehicle may still be drivable, improper transmission operation can lead to further damage.
Driving with a malfunctioning transmission can be unsafe and may lead to further vehicle damage. Have the issue diagnosed and repaired promptly.
• Vehicle engine running
• Transmission in drive
The Transmission Control Module is typically located near the transmission or in the engine compartment.
Q: Can I drive with a P1698 code?
A: It's possible to drive with this code, but it is not recommended as it may lead to further damage or unsafe driving conditions.
Q: Will clearing the code fix the problem?
A: Clearing the code may turn off the Check Engine Light temporarily, but it will not fix the underlying issue.
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