7A2-56 TRANSMISSION CONTROL SYSTEM (JR405E)
51. Test the control circuit between the TCM (pin
23 of C-95) and the in-line harness connector
(pin 6 of E-54 female side) for a short to
battery or ignition voltage.
2. Repair the circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 12 Go to Step 11
6 1. Test the control circuit between the TCM (pin
23 of C-95) and the in-line harness connector
(pin 6 of E-54 female side) for the following
conditions:
• An open circuit
• A short to ground
• High resistance
2. Repair the circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 12 Go to Step 7
7 1. Turn OFF the ignition.
2. Disconnect the TCM harness connector.
3. Inspect for an intermittent and for a poor connection at the harness connector of the
TCM (pin 23 of C-95).
4. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 12 Go to Step 11
8 1. Inspect for an intermittent and for a poor
connection at the in-line harness connector
(pin 6 of E-54).
2. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 12 Go to Step 9
9 1. Remove the transmission oil pan. Refer to
repair instructions (On-Vehicle Service).
2. Inspect the PC solenoid valve for the following conditions:
• Physical damage of solenoid valve
• Loose or improper installation of solenoid valve
3. Inspect for an intermittent and for a poor connection at the in-line harness connector.
4. Test the control circuit between the PC solenoid valve and the in-line harness
connector (pin 6 of E-54 male side) for the
following conditions:
• An open circuit
• A short to ground
• A short to the other solenoid valve circuit
• High resistance
5. Repair the connection(s) or circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 12 Go to Step 10
10 Replace the PC solenoid valve. Refer to repair
instructions (On-Vehicle Service).
Did you complete the replacement? —
Go to Step 12 —
Step
Action Value(s)Yes No
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-59
41. Turn OFF the ignition.
2. Disconnect the in-line harness connector (E- 54) near the transmission range switch.
3. Connect a test lamp between the control circuit (pin 5 of E-54 female side) and a known
good ground.
4. Turn ON the ignition, with the engine OFF.
5. Perform the Low & Reverse Brake Solenoid control with a scan tool.
6. Command the solenoid valve ON and OFF.
Does the test lamp turn ON and OFF with each
command? —
Go to Step 9 Go to Step 5
5 Does the test lamp remain illuminated with each
command? —
Go to Step 6 Go to Step 7
6 1. Test the control circuit between the TCM (pin 6
of C-95) and the in-line harness connector (pin
5 of E-54 female side) for a short to battery or
ignition voltage.
2. Repair the circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 13 Go to Step 12
7 1. Test the control circuit between the TCM (pin 6
of C-95) and the in-line harness connector (pin
5 of E-54 female side) for the following
conditions:
• An open circuit
• A short to ground
• High resistance
2. Repair the circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 13 Go to Step 8
8 1. Turn OFF the ignition.
2. Disconnect the TCM harness connector.
3. Inspect for an intermittent and for a poor connection at the harness connector of the
TCM (pin 6 of C-95).
4. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 13 Go to Step 12
9 1. Inspect for an intermittent and for a poor
connection at the in-line harness connector
(pin 5 of E-54).
2. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 13 Go to Step 10
Step
Action Value(s)Yes No
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
7A2-62 TRANSMISSION CONTROL SYSTEM (JR405E)
41. Turn OFF the ignition.
2. Disconnect the in-line harness connector (E- 54) near the transmission range switch.
3. Connect a test lamp between the control circuit (pin 9 of E-54 female side) and a known
good ground.
4. Turn ON the ignition, with the engine OFF.
5. Perform the 2-4 Brake Solenoid control with a scan tool.
6. Command the solenoid valve ON and OFF.
Does the test lamp turn ON and OFF with each
command? —
Go to Step 9 Go to Step 5
5 Does the test lamp remain illuminated with each
command? —
Go to Step 6 Go to Step 7
6 1. Test the control circuit between the TCM (pin 7
of C-95) and the in-line harness connector (pin
9 of E-54 female side) for a short to battery or
ignition voltage.
2. Repair the circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 13 Go to Step 12
7 1. Test the control circuit between the TCM (pin 7
of C-95) and the in-line harness connector (pin
9 of E-54 female side) for the following
conditions:
• An open circuit
• A short to ground
• High resistance
2. Repair the circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 13 Go to Step 8
8 1. Turn OFF the ignition.
2. Disconnect the TCM harness connector.
3. Inspect for an intermittent and for a poor connection at the harness connector of the
TCM (pin 7 of C-95).
4. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 13 Go to Step 12
9 1. Inspect for an intermittent and for a poor
connection at the in-line harness connector
(pin 9 of E-54).
2. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 13 Go to Step 10
Step
Action Value(s)Yes No
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-65
41. Turn OFF the ignition.
2. Disconnect the in-line harness connector (E- 54) near the transmission range switch.
3. Connect a test lamp between the control circuit (pin 10 of E-54 female side) and a
known good ground.
4. Turn ON the ignition, with the engine OFF.
5. Perform the High Clutch Solenoid control with a scan tool.
6. Command the solenoid valve ON and OFF.
Does the test lamp turn ON and OFF with each
command? —
Go to Step 9 Go to Step 5
5 Does the test lamp remain illuminated with each
command? —
Go to Step 6 Go to Step 7
6 1. Test the control circuit between the TCM (pin 8
of C-95) and the in-line harness connector (pin
10 of E-54 female side) for a short to battery
or ignition voltage.
2. Repair the circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 13 Go to Step 12
7 1. Test the control circuit between the TCM (pin 8
of C-95) and the in-line harness connector (pin
10 of E-54 female side) for the following
conditions:
• An open circuit
• A short to ground
• High resistance
2. Repair the circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 13 Go to Step 8
8 1. Turn OFF the ignition.
2. Disconnect the TCM harness connector.
3. Inspect for an intermittent and for a poor connection at the harness connector of the
TCM (pin 8 of C-95).
4. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 13 Go to Step 12
9 1. Inspect for an intermittent and for a poor
connection at the in-line harness connector
(pin 10 of E-54).
2. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 13 Go to Step 10
Step
Action Value(s)Yes No
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
7A2-68 TRANSMISSION CONTROL SYSTEM (JR405E)
41. Turn OFF the ignition.
2. Disconnect the in-line harness connector (E- 54) near the transmission range switch.
3. Connect a test lamp between the control circuit (pin 3 of E-54 female side) and a known
good ground.
4. Turn ON the ignition, with the engine OFF.
5. Perform the Low Clutch Solenoid control with a scan tool.
6. Command the solenoid valve ON and OFF.
Does the test lamp turn ON and OFF with each
command? —
Go to Step 9 Go to Step 5
5 Does the test lamp remain illuminated with each
command? —
Go to Step 6 Go to Step 7
6 1. Test the control circuit between the TCM (pin 9
of C-95) and the in-line harness connector (pin
3 of E-54 female side) for a short to battery or
ignition voltage.
2. Repair the circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 13 Go to Step 12
7 1. Test the control circuit between the TCM (pin 9
of C-95) and the in-line harness connector (pin
3 of E-54 female side) for the following
conditions:
• An open circuit
• A short to ground
• High resistance
2. Repair the circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 13 Go to Step 8
8 1. Turn OFF the ignition.
2. Disconnect the TCM harness connector.
3. Inspect for an intermittent and for a poor connection at the harness connector of the
TCM (pin 9 of C-95).
4. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 13 Go to Step 12
9 1. Inspect for an intermittent and for a poor
connection at the in-line harness connector
(pin 3 of E-54).
2. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 13 Go to Step 10
Step
Action Value(s)Yes No
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
7A2-82 TRANSMISSION CONTROL SYSTEM (JR405E)
51. Test the control circuit between the TCM (pin
17 of C-95) and the in-line harness connector
(pin 4 of E-54 female side) for a short to
battery or ignition voltage.
2. Repair the circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 12 Go to Step 11
6 1. Test the control circuit between the TCM (pin
17 of C-95) and the in-line harness connector
(pin 4 of E-54 female side) for the following
conditions:
• An open circuit
• A short to ground
• High resistance
2. Repair the circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 12 Go to Step 7
7 1. Turn OFF the ignition.
2. Disconnect the TCM harness connector.
3. Inspect for an intermittent and for a poor connection at the harness connector of the
TCM (pin 17 of C-95).
4. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 12 Go to Step 11
8 1. Inspect for an intermittent and for a poor
connection at the in-line harness connector
(pin 4 of E-54).
2. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 12 Go to Step 9
9 1. Remove the transmission oil pan. Refer to
repair instructions (On-Vehicle Service).
2. Inspect the TCC solenoid valve for the following conditions:
• Physical damage of solenoid valve
• Loose or improper installation of solenoid valve
3. Inspect for an intermittent and for a poor connection at the harness connector of the
TCC solenoid valve or in-line harness
connector.
4. Inspect for an intermittent and for a poor connection of ground wire.
5. Test the control circuit between the TCC solenoid valve and the in-line harness
connector (pin 4 of E-54 male side) for the
following conditions:
• An open circuit
• A short to ground
• A short to the other solenoid valve circuit
• High resistance
6. Repair the connection(s) or circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 12 Go to Step 10
Step
Action Value(s)Yes No
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-87
DTC P1875 (Flash Code 25)
Circuit Description
The all shift solenoid valves feed drive voltage from the
TCM and low side circuit is connected to the TCM
through the ground return circuit. The TCM monitors
the ground return circuit through the feedback circuit. If
the TCM detects an improper status on the ground
return circuit, this DTC will set.
Condition for Running the DTC • The ignition switch is ON.
Condition for Setting the DTC • The TCM detects an open circuit on the ground return circuit.
Action Taken When the DTC Sets • The TCM blinks the Check Trans lamp when the diagnostic runs and fails.
• The TCM stops all shift solenoid valves and fixes to the 3rd gear. If a fail-safe valve problem is
detected, the shift solenoid valves are not stopped
but gear is fixed to the 3rd gear. • The TCM stops PC solenoid valve.
• The TCM inhibits lock up control.
Condition for Clearing the DTC • The TCM turns OFF the Check Trans lamp when the diagnostic runs and does not fail at next
ignition cycle.
• A current DTC clears when the diagnostic runs and does not fail at next ignition cycle.
Diagnostic Aids • If an intermittent condition is suspected, refer to Intermittent Conditions in this section.
Schematic Reference: Transmission Controls
Schematics
Connector End View Reference: Transmission
Controls Connector End Views or TCM Connector End
Views
Circuit/ System Testing DTC P1875
Step Action Value(s)Yes No
1 Did you perform the Diagnostic System Check -
Transmission Controls? —
Go to Step 2 Go to Diagnostic
System Check -
Transmission Controls
2 1. Install a scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Start the engine.
4. Monitor the DTC Information with a scan tool.
Does the DTC fail this ignition? —
Go to Step 3 Go to Diagnostic
Aids
3 1. Turn OFF the ignition.
2. Disconnect the in-line harness connector (E- 54) near the transmission range switch.
3. Connect a test lamp between the ground return circuit (pin 11 of E-54 male side) and
battery voltage.
Does the test lamp illuminate? —
Go to Step 4 Go to Step 7
4 1. Inspect for an intermittent and for a poor
connection at the in-line harness connector
(pin 11 of E-54).
2. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 9 Go to Step 5
5 1. Test the circuit between the TCM (pin 22 of C-
95) and the in-line harness connector (pin 11
of E-54 female side) for an open circuit or high
resistance.
2. Repair the circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 9 Go to Step 6
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-91
17Repair the short to battery or ignition voltage
between the TCM (pin 20 of C-94) and the IP
cluster (pin 25 of B-23).
Did you complete the repair? —
Go to Step 21 —
18 Repair the open circuit or high resistance on
ignition the voltage feed circuit between the Meter
(10A) fuse and the IP cluster (pin 8 of B-24).
Did you complete the repair? —
Go to Step 21 —
19 Repair or replace the IP cluster.
Did you complete the repair or replacement? —
Go to Step 21 —
20 Important:
Replacement TCM must be
programmed.
Replace the TCM. Refer to TCM Replacement.
Did you complete the replacement? —
Go to Step 21 —
21 1. Reconnect all previously disconnected fuse or
harness connector(s).
2. Perform the Check Light control with a scan tool.
3. Command the lamp ON and OFF.
Does the check trans lamp turn ON and OFF with
each command? —
System OK Go to Step 7
Step
Action Value(s)Yes No
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007