Diagnostic Test

WARNING: This page is about a different car, the 2010 Dodge Charger and 2010 Chrysler 300. However, it is still accessible from the selected car via links, so may be relevant.

VERIFY DTC IS ACTIVE
NOTE:
- To help in the service of the ACC System, it is recommended speaking to the customer to find out what type of environment they were driving in when the cruise concern took place. Heavy rain, snow, ice, and fog can cause the ACC system to become unavailable. This should be considered normal operation and no repair is necessary.
- Vehicles that have had the suspension modified and/or a aftermarket grill installed that blocks the ACC sensor can cause the ACC system not to operate properly.
1. Ignition on, engine not running.
2. Using a scan tool, read ACC DTCs.
  Is the DTC active at this time?
  
  Yes
  - Go to step 2
  No
  - The conditions that caused this code to set are not present at this time. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors, pay particular attention the both CAN circuits.
  - Perform the ACC MODULE VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Adaptive Cruise Control (ACC) - Standard Procedure .
CHECK (F202) FUSED IGNITION CIRCUIT

Fig 1: Checking Fused Ignition Circuit
Courtesy of CHRYSLER LLC
1. Turn the ignition off.
2. Disconnect the ACC Module harness connector.
3. Start the engine.
  NOTE: It may be necessary to wiggle the wiring harness while performing the test light procedure. If the test light illuminates and then goes out while wiggling the harness, inspect the harness in that area for wire damage.
4. Using a test light connected to ground, probe the (F202) Fused Ignition circuit at the ACC Module harness connector.
  NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.
  
  Does the test light illuminate brightly?
  
  Yes
  - Go to step 3
  No
  - Repair the (F202) Fused Ignition circuit.
  - Perform the ACC MODULE VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Adaptive Cruise Control (ACC) - Standard Procedure .
CHECK (Z901) GROUND CIRCUIT

Fig 2: Checking Ground Circuit
Courtesy of CHRYSLER LLC
1. Turn the ignition off.
  NOTE: It may be necessary to wiggle the wiring harness while performing the test light procedure. If the test light illuminates and then goes out while wiggling the harness, inspect the harness in that area for wire damage.
2. Using a test light connected to battery voltage, probe the (Z901) Ground circuit.
  NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.
  
  Does the test light illuminate brightly?
  
  Yes
  - Replace the ACC Module in accordance with the Service Information.
  - Perform the ACC MODULE VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Adaptive Cruise Control (ACC) - Standard Procedure .
  No
  - Repair the (Z901) Ground circuit.
  - Perform the ACC MODULE VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Adaptive Cruise Control (ACC) - Standard Procedure .