B2542
B2542-CONVERTIBLE TOP SENSE LIMIT SWITCH CIRCUIT LOW
Theory of Operation
The Convertible Top on the Sebring Convertible is fairly typical of convertible tops. There are three types of failures possible: Electrical failure (switches, wiring, motor, etc.), Hydraulic failure (fluid level low, leaks, pump internal, etc.), and Mechanical failure (binding roof, bent links, obstructions, etc.). Each type of failure mode will be rationalized by the power Top Control Module (PTCM) and labeled with a DTC. The DTCs set by the PTCM can also be considered to have three types of failure modes:
- Performance - These are time out DTCs, meaning the system timed out waiting for the next switch in sequence to change state. When the PTCM does not get the state change in the expected amount of time, it assumes something may be wrong and stops any further top operation in that direction. Typically the pump will run for 10 second before it times out.
- Circuit Low - These DTCs set for a circuit that stays active at all times, meaning the signal circuit to the specified switch is continuously grounded. This could relate to a short to ground on the signal circuit, a sticking switch, or even a mechanical issue not allowing the switch to become inactive.
- Correlation - These DTCs specifically relate two switches in a subcomponent (deck lid, tonneau drive, header latch, etc.) of the convertible top system. Both of the specified switches will be active in one position of the subcomponent (extended, retracted, open, closed, etc.). The switch that will not change state while attempting to operate the convertible top system, is the most likely area for attention.
- When Monitored:
With the Ignition Switch in the on position and the Power Top Control Module (PTCM) awake.
- Set Condition:
This code will set when there is a timeout in the roof sequence because the Roof Sense Limit Switch is stuck active or shorted to ground for at least 40 ms.
Always perform the Power Top System Pre-Diagnostic procedure before proceeding. Power Top System Pre-Diagnostic Procedure.
1. TEST FOR INTERMITTENT CONDITION
NOTE: The PTCM will only set this fault code when the top operation times out. Maximum timeout is 30 seconds.
1. Turn the ignition on.
2. With the scan tool, record and erase all PTCM DTCs.
3. Try to operate the Power Top Switch in the open direction for a minimum of 30 seconds.
4. Try to operate the Power Top Switch in the closed direction for a minimum of 30 seconds.
5. With the scan tool, read all PTCM DTCs.
Does the scan tool display this DTC as active?
Yes
- Go To 2
No
- The condition that caused this symptom is currently not present. With the scan tool, check the Environmental Data to help identify the conditions in which the DTC was set. Check for an intermittent condition by inspecting the related wiring harness for chafed, pierced, pinched, and partially broken wires. Also, inspect the related connectors for broken, bent, pushed out, spread, corroded, or contaminated terminals. Repair as necessary.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
2. ROOF SENSE LIMIT SWITCH
1. Operate the Power Top Switch to open the roof off of the Header.
2. Turn the ignition off.
3. Disconnect the PTCM C1 harness connector.
4. Using an ohmmeter, measure the resistance to ground on the (Q970) Roof Sense Limit Switch Signal circuit while toggling the Roof Sense Limit Switch.
Does the resistance toggle between less than 20.0 Ohms to greater than 10K Ohms?
Yes
- Replace the PTCM.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
No
- Go To 3
3. (Q970) ROOF SENSE LIMIT SWITCH CIRCUIT SHORTED TO GROUND
1. Disconnect the Roof Sense Limit Switch harness connector.
2. Measure the resistance between ground and the (Q970) Roof Sense Limit Switch Signal circuit.
Is the resistance below 10K Ohms?
Yes
- Repair the (Q970) Roof Sense Limit Switch Signal circuit for a short to ground.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
No
- Replace the Roof Sense Limit Switch.
- Perform the BODY VERIFICATION TEST. Body Verification Test.