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B18D7

B18D7-CONVERTIBLE TOP CONTROL CIRCUIT LOW/OPEN

B18D7 - Convertible Top Control Circuit Low/Open:






WHEN MONITORED
Whenever the module is awake.

SET CONDITION
If the Left Window Regulator Module does not sense any (0.0) voltage on either the Top Down or Top Up Relay Control circuit, this code will set.

POSSIBLE CAUSES
- Trouble code present
- TIPM fuse no. 1 (power top) open
- Relay fused B+ circuit open
- Top down relay control wire short to ground
- Top up relay control wire short to ground
- Top down relay control wire open
- Top down relay open
- Top up relay control wire open
- Top up relay open
- Window regulator module

Diagnostic Test

1. DTC PRESENT

With the scan tool, record and erase DTC's.
Cycle the ignition switch from On to Off.
Operate the Power Top down and up.
Wait one minute.
With the scan tool, read DTCs.

Q: Does the scan tool display B18D7 CONVERTIBLE TOP CIRCUIT LOW/OPEN?

YES: Go To 2
NO: The conditions that caused this code to set is not present at this time. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors for a intermittent condition. Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test

2. POWER TOP FUSE OPEN

Test the Power Top Feed fuse No. 1 in the TIPM.

Q: Is the fuse open?

YES: Replace the fuse and operate the power top several times. If the fuse blows again, use the wiring diagram/schematic as a guide to locate the shorted circuit. Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Go To 3




3. FUSED B+ CIRCUIT OPEN

Disconnect the Power Top Relay (at the Pump assembly).

NOTE: Ensure the fuse is installed before continuing.

Turn the ignition on.
Measure the voltage between Fused B+ circuit and ground at the Power Top Relay.

Q: Is the voltage above 11.0 volts?

YES: Go To 4
NO: Repair the Fused B+ circuit for an open. Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test




4. TOP DOWN RELAY CONTROL WIRE SHORT TO GROUND

Turn the ignition off.
Disconnect the Left Window Regulator Module connector.
Measure the resistance between ground and the Top Down Relay Control circuit.

Q: Is the resistance below 1,000.0 ohms?

YES: Repair the Top Down Relay Control circuit for a short to ground. Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Go To 5




5. TOP UP RELAY CONTROL WIRE SHORT TO GROUND

Measure the resistance between ground and the Top Up Relay Control circuit.

Q: Is the resistance below 1,000.0 ohms?

YES: Repair the Top Up Relay Control circuit for a short to ground. Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Go To 6




6. TOP DOWN RELAY CONTROL CIRCUIT OPEN

NOTE: Ensure the Power Top Relay (at the Pump assembly) is connected before proceeding.

Turn the ignition on.
Measure the voltage between Ground and the Top Down Relay Control circuit in the Window Regulator Module connector.

Q: Is the voltage above 11.0 volts?

YES: Go To 7
NO: Go To 9




7. TOP UP RELAY CONTROL CIRCUIT OPEN

Measure the voltage between Ground and the Top Up Relay Control circuit in the Window Regulator Module connector.

Q: Is the voltage above 11.0 volts?

YES: Replace the Window Regulator Module. Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Go To 8




8. TOP UP RELAY CONTROL WIRE OPEN

Turn the ignition off.
Measure the resistance of the Top Up Relay Control circuit between the relay connector and the module connector.

Q: Is the resistance below 5.0 ohms?

YES: Replace the Power Top Relay. Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Repair the Top Up Relay Control circuit for an open. Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test




9. TOP DOWN RELAY CONTROL WIRE OPEN

Turn the ignition off.
Measure the resistance of the Top Down Relay Control circuit between the relay connector and the module connector.

Q: Is the resistance below 5.0 ohms?

YES: Replace the Power Top Relay. Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Repair the Top Down Relay Control wire for an open. Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test