What Does P1642 Mean?
Communication failure has been detected on the CAN bus network between the Engine Control Module and the Anti-lock Brake System Control Module. This network malfunction prevents proper data exchange between these critical safety and powertrain systems.
Safety Warning
Critical safety concern. ABS, stability control, and traction control may be disabled. Vehicle may enter limp mode with reduced power and functionality.
Common Causes
35%
Open or short circuit in CAN bus wiring between ECM and ABS module
25%
Faulty ABS control module with defective CAN transceiver
20%
Missing or incorrect CAN bus termination resistors
15%
Corroded or loose module connectors at ECM or ABS module
5%
ECM internal CAN communication circuit failure
Diagnostic Steps
1
Step 1: Check ABS module for separate communication codes and verify module is powered
2
Step 2: Measure CAN High and CAN Low resistance between ECM and ABS module (should be 60 ohms with key off)
3
Step 3: Check for proper voltage on CAN lines (should be approximately 2.5V each with key on)
4
Step 4: Inspect all connectors and pins for corrosion, pushed-back pins, or physical damage
5
Step 5: Use oscilloscope to verify CAN signal integrity if basic voltage tests pass
Estimated Repair Cost
$200 - $1,500
Parts + labor, varies by vehicle and location
Communication failure has been detected on the CAN bus network between the Engine Control Module and the Anti-lock Brake System Control Module. This network malfunction prevents proper data exchange between these critical safety and powertrain systems.
The most common cause of P1642 (Can Link ECM/ABSCM Circuit / Network Malfunction) is: Open or short circuit in CAN bus wiring between ECM and ABS module
Typical repair costs for P1642 range from $200 to $1,500, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Critical safety concern. ABS, stability control, and traction control may be disabled. Vehicle may enter limp mode with reduced power and functionality.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P1642 to identify the root cause.
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Quick Info
Category
Powertrain
System
CAN Bus Network Communication
Difficulty
Type
Manufacturer
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