GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC B1325 03: Device Power 1 Circuit Voltage Below Threshold

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

B+, FTC Module X1 Terminal 24

1

1

--

--

B+, FTC Module X1 Terminal 26

B1335 03, B3860 02

B1335 03

--

--

12-Volt Reference

B1395 02

B1296 06, B3669 06

--

--

Serial Data, FTC Module X1 Terminal 1

1

--

1

--

Serial Data, FTC Module X1 Terminal 2

1

--

1

--

Serial Data, FTC Module X1 Terminal 11

B316A 02

2

B316A 01

--

Serial Data, FTC Module X1 Terminal 23

B316A 02

3

B316A 01

--

Signal, FTC Module X1 Terminal 4

B3685 59, B1010 08

B3685 59

--

--

Signal, FTC Module X1 Terminal 5

4

4

--

--

Signal, FTC Module X1 Terminal 10

B3602 02

4

--

--

Signal, FTC Module X1 Terminal 16

B3683 59, B1010 08

B3683 59, B1010 08

--

--

Signal, FTC Module X1 Terminal 17

B366C 59

B1010 08

--

--

Signal, FTC Module X1 Terminal 22

B3602 02

4

--

--

Signal, FTC Module X2 Terminal 7

B366D 59

B366D 59

--

--

Signal, FTC Module X2 Terminal 8

B366A 59

B366A 59

--

--

Signal, FTC Module X2 Terminal 11

B3669 06

B3669 06

B3669 01

--

Signal, FTC Module X2 Terminal 12

B1395 02

B367B 59

--

--

Signal, FTC Module X2 Terminal 17

B367F 59, B1010 08

B367F 59, B1010 08

--

--

Signal, FTC Module X2 Terminal 18

B1307 59

B1307 59

--

--

Signal, FTC Module X2 Terminal 19

B366E 59

B366E 59

--

--

Signal, FTC Module X2 Terminal 20

B366B 59

B366B 59

--

--

Signal, FTC Module X2 Terminal 23

B1296 06

B1296 06

B1296 01

--

Signal, FTC Module X2 Terminal 24

B367A 59

B1395 02

--

--

Valve 1 Control

B3674 02

B3674 04

B3674 01

--

Valve 2 Control

B3674 02

B3674 04

B3674 01

--

Folding Top Pump Motor Direction A Voltage Control

B3680 02

B3680 04

B3680 01

--

Folding Top Pump Motor Direction B Voltage Control

B3680 02

B3680 04

B3680 01

--

Low Reference Circuit

--

B3674 01, B3675 01, B1010 08

4

--

Ground, FTC Module X1 Terminal 25

--

B1345 04

--

--

Ground, FTC Module X1 Terminal 27

--

1

--

--

1. No Communication With FTC Module

2. Passenger Side Windows Inoperative During Top Operation

3. Driver Side Windows Inoperative During Top Operation

4. Folding Top Malfunction

Circuit/System Description

The folding top control (FTC) module receives B+ on X1, terminal 24 for use in logic functions. The FTC Module monitors this circuit for proper operation.

Conditions for Running the DTC

The FTC module is active.

Conditions for Setting the DTC

Voltage is less than 9 volts when active or 10 volts when inactive.

Action Taken When the DTC Sets

The top is disabled.

Conditions for Clearing the DTC

The fault is no longer present and the top completes one cycle.

Diagnostic Aids

A weak battery can cause DTC B1325 03 to set.

Reference Information

Schematic Reference

Folding Top Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Power Folding Top Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Testing

  1. Ignition OFF, disconnect the X1 harness connector at the folding top control module.
  2. Ignition ON, test for greater than 10 volts between the B+ circuit terminal 24 and ground.
  3. If not within the specified range, test the B+ circuit for a short to ground or an open/high resistance.
  4. If all circuits tests normal, replace the FTC module.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for folding top control module replacement, setup, and programming