DTC P1870 Transmission Component Slipping 2.2L
DTC P1870 Range Reference Thumbnail 4L60-E
Range
| Gear
| Shift Solenoid
| TCC Solenoid
| TCC PWM Solenoid
| 2-4 Band
| Forward Clutch
| 3-4 Clutch
| Torque Converter Clutch
|
1-2
| 2-3
|
Overdrive
| 4th
| ON
| OFF
| ON
| 90% (ON)
| Applied
| Applied
| Applied
| Applied
|
Circuit Description
The PCM monitors the difference between engine speed and transmission
output speed. In D3 drive range with the TCC engaged, the engine speed should
closely match the transmission output speed. In D4 drive range, with the TCC
engaged, the TCC slip speed should be -20 to +20 RPM.
When the PCM detects excessive TCC slip when the TCC should be engaged,
then DTC P1870 sets. DTC P1870 is a type B DTC.
Conditions for Setting the DTC
DTC P1870 sets if the following conditions are met for three TCC cycles
with reported excessive TCC slip conditions, two consecutive times.
| • | No TP DTCs P0122 or P0123. |
| • | No VSS Assy. DTCs P0502 or P0503. |
| • | No 1-2 SS Valve DTC P0753. |
| • | No 2-3 SS Valve DTC P0758. |
| • | The engine speed is greater than 450 RPM for 8 seconds. |
| • | The vehicle speed is 56-105 km/h (35-65 mph). |
| • | The speed ratio is 0.64-0.95 (the speed ratio is the engine
speed divided by the output speed). |
| • | The engine speed is 1500-3500 RPM. |
| • | The engine vacuum is 0-105 kPa. |
| • | The engine torque is 40-400 lbs ft. |
| • | The TP angle is 16-50%. |
| • | The TFT is between 20-130°C (68-266°F). |
| • | TCC is commanded On for 5 seconds. |
| • | The TCC is at maximum apply for 5 seconds. |
| • | The shift solenoid performance diagnostic counters are zero. |
| • | The TCC slip speed is 300-1000 RPM. |
| • | All conditions met for 7 seconds. |
Action Taken When the DTC Sets
| • | The PCM inhibits TCC engagement. |
| • | The PCM commands maximum line pressure. |
| • | The PCM inhibits 4th gear if the transmission is in hot mode. |
| • | The PCM freezes shift adapts from being updated. |
| • | The PCM illuminates the Malfunction Indicator Lamp (MIL). |
Conditions for Clearing the MIL/DTC
| • | The PCM turns OFF the MIL after three consecutive ignition cycles
without a failure reported. |
| • | A scan tool can clear the DTC from the PCM history. The PCM clears
the DTC from the PCM history if the vehicle completes 40 warm-up cycles without
a failure reported. |
| • | The PCM cancels the DTC default actions when the fault no longer
exists and the ignition is OFF long enough in order to power down the PCM. |
Diagnostic Aids
Internal transmission failures could set DTC P1870.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step tests the torque converter for slippage while in a commanded lock-up
state.
DTC P1870 Transmission Slipping Component (2.2L)
Step
| Action
| Value(s)
| Yes
| No
|
1
| Was the Powertrain On-Board
Diagnostic (OBD) System Check performed?
| --
|
Go to Step 2
| Go to Powertrain OBD System
Check
|
2
| Perform the transmission fluid checking procedure. Refer to 4L60-E Transmission
Fluid Checking Procedure.
Did you perform the fluid checking procedure?
| --
|
Go to Step 3
| Go to 4L60-E Transmission
Fluid Checking Procedure
|
3
|
- Install the scan tool.
- With the engine OFF, turn the ignition switch to the RUN position.
Important: Before clearing the DTCs, use the scan tool in order to record the Freeze
Frame and Failure Records for reference. The Clear Info function will erase
the data.
- Record the DTC Freeze Frame and Failure Records.
- Drive the vehicle in 4th gear with the TCC engaged.
Is the TCC Slip Speed between the specified values for 7 seconds?
| 300-1000 RPM
|
Go to Step 4
| Go to Diagnostic Aids
|
4
|
- Inspect the Torque Converter Clutch Solenoid Valve (TCC Sol. Valve)
for the following conditions:
| • | Internal malfunction (such as sediment or damage) |
- Inspect the Torque Converter Clutch Pulse Width Modulation Solenoid
Valve (TCC PWM Sol. Valve) for the following conditions:
| • | Internal malfunction (such as sediment or damage) |
Did you find a problem?
| --
|
Go to Step 13
|
Go to Step 5
|
5
|
- Inspect the 1-2 Shift Solenoid Valve (1-2 SS Valve) for the following
conditions:
| • | Internal malfunction (such as sediment or damage) |
- Inspect the 2-3 Shift Solenoid Valve (2-3 SS Valve) for the following
conditions:
| • | Internal malfunction (such as sediment or damage) |
Did you find a problem?
| --
|
Go to Step 13
|
Go to Step 6
|
6
| Inspect the valve body assembly for a stuck TCC signal valve. Refer
to Unit Repair.
Did you find a problem?
| --
|
Go to Step 13
|
Go to Step 7
|
7
| Inspect the torque converter assembly for the following conditions:
| • | Stator roller clutch not holding |
Did you find a problem?
| --
|
Go to Step 13
|
Go to Step 8
|
8
| Inspect the oil pump assembly for the following conditions:
| • | Stuck converter clutch valve |
| • | Converter clutch valve assembled backwards |
| • | Mispositioned converter clutch valve retaining ring |
| • | Mispositioned pump to case gasket |
| • | Restricted orifice cup plugs |
| • | Damaged orifice cup plugs |
| • | Over-tightened, or unevenly tightened pump body to cover bolts |
Refer to Unit Repair.
Did you find a problem?
| --
|
Go to Step 13
|
Go to Step 9
|
9
| Inspect the input housing and shaft assembly for the following conditions:
| • | Cut turbine shaft o-ring seal |
| • | Damaged turbine shaft o-ring seal |
| • | Restricted turbine shaft retainer and ball assembly |
| • | Damaged turbine shaft retainer and ball assembly |
Refer to Unit Repair.
Did you find a problem?
| --
|
Go to Step 13
|
Go to Step 10
|
10
| Inspect the 2-4 band assembly for the following conditions:
| • | The band anchor pin is not engaged. |
| • | Restricted apply passages in the 2-4 servo assembly |
| • | Blocked apply passages in the 2-4 servo assembly |
| • | Nicks or burrs on the servo pin |
| • | Nicks or burrs on the pin bore in the case |
| • | Damaged fourth servo piston |
| • | Misassembled fourth servo piston |
| • | Incorrect band apply pin |
| • | Damaged servo bore in the case |
| • | Porosity in the pistons |
| • | Damaged piston seal grooves |
| • | Plugged orifice cup plug |
| • | Missing orifice cup plug |
Refer to Unit Repair.
Did you find a problem?
| --
|
Go to Step 13
|
Go to Step 11
|
11
| Inspect the forward clutch assembly for the following conditions:
| • | Porosity in the forward clutch piston |
| • | Damaged forward clutch piston |
| • | Missing forward clutch piston inner and outer seals |
| • | Cut forward clutch piston inner and outer seals |
| • | Damaged forward clutch piston inner and outer seals |
| • | Missing input housing to forward clutch housing o-ring seal |
| • | Cut input housing to forward clutch housing o-ring seal |
| • | Damaged input housing to forward clutch housing o-ring seal |
| • | Damaged forward clutch housing |
| • | Damaged forward clutch housing retainer and ball assembly |
| • | Forward clutch housing retainer and ball assembly is not sealing. |
Refer to Unit Repair.
Did you find a problem?
| --
|
Go to Step 13
|
Go to Step 12
|
12
| Inspect the 3-4 clutch assembly for the following conditions:
| • | Porosity in the 3-4 clutch piston |
| • | Damaged 3-4 clutch piston |
| • | Missing 3-4 clutch inner and outer seals |
| • | Cut 3-4 clutch inner and outer seals |
| • | Damaged 3-4 clutch inner and outer seals |
| • | Damaged 3-4 clutch spring assembly |
| • | Damaged 3-4 clutch apply ring |
| • | Damaged piston seal grooves |
| • | Plugged orifice cup plug |
| • | Missing orifice cup plug |
Refer to Unit Repair.
Did you find a problem?
| --
|
Go to Step 13
| Go to Diagnostic Aids
|
13
| In order to verify your
repair, perform the following procedure:
- Select DTC.
- Select Clear Info.
- Operate the vehicle under the following conditions:
| • | Drive the vehicle in D4, with the TCC ON, and a throttle position
of 16-50%. |
| • | Ensure that the TCC Slip Speed is -20 to +40 RPM
for at least 7 seconds. |
- Select Specific DTC. Enter DTC P1870.
Has the test run and passed?
| --
| System
OK
| Begin the diagnosis
again. Go to Step 1
|
DTC P1870 Transmission Component Slipping 4.3L
DTC P1870 Range Reference Thumbnail 4L60-E
Range
| Gear
| Shift Solenoid
| TCC Solenoid
| TCC PWM Solenoid
| 2-4 Band
| Forward Clutch
| 3-4 Clutch
| Torque Converter Clutch
|
1-2
| 2-3
|
Overdrive
| 4th
| ON
| OFF
| ON
| 90% (ON)
| Applied
| Applied
| Applied
| Applied
|
Circuit Description
The VCM monitors the difference between engine speed and transmission
output speed. In D3 drive range with the TCC engaged, the engine speed should
closely match the transmission output speed. In D4 drive range, with the
TCC engaged, the TCC slip speed should be -20 to +20 RPM.
When the VCM detects excessive TCC slip when the TCC should be engaged,
then DTC P1870 sets. DTC P1870 is a type B DTC.
Conditions for Setting the DTC
DTC P1870 sets if the following conditions are met for three TCC cycles
with reported excessive TCC slip conditions, two consecutive times.
| • | No TP DTCs P0122 or P0123. |
| • | No VSS Assy. DTC P0502. |
| • | No TFT Sensor DTCs P0712 or P0713. |
| • | No TCC Sol. Valve DTC P0740. |
| • | No 1-2 SS Valve DTCs P0751 or P0753. |
| • | No 2-3 SS Valve DTCs P0756 or P0758. |
| • | No TFP Val. Position Sw. DTC P1810. |
| • | No TCC PWM Sol. Valve DTC P1860. |
| • | The engine speed is greater than 450 RPM for 8 seconds. |
| • | The engine torque is 50-450 lb ft. |
| • | The TFT is 20-130°C (68-266°F). |
| • | The TCC is ON for 5 seconds. |
| • | The TCC is at maximum apply for 5 seconds. |
| • | The TCC slip speed is greater than 130 RPM. |
| • | All conditions met for 7 seconds. |
Action Taken When the DTC Sets
| • | The VCM inhibits TCC engagement. |
| • | The VCM commands maximum line pressure. |
| • | The VCM inhibits 4th gear if the transmission is in hot mode. |
| • | The VCM freezes shift adapts from being updated. |
| • | The VCM illuminates the Malfunction Indicator Lamp (MIL). |
Conditions for Clearing the MIL/DTC
| • | The VCM turns OFF the MIL after three consecutive ignition cycles
without a failure reported. |
| • | A scan tool can clear the DTC from the VCM history.
The VCM clears the DTC from the VCM history if the vehicle completes 40 warm-up
cycles without a failure reported. |
| • | The VCM cancels the DTC default actions when the fault no longer
exists and the ignition is OFF long enough in order to power down the VCM. |
Diagnostic Aids
| • | Internal transmission failures could set a DTC P1870. |
| • | A TFP Valve Position Switch malfunction could set a DTC P1870. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step tests the torque converter for
slippage while in a commanded lock-up state.
DTC P1870 Transmission Slipping Component (4.3L)
Step
| Action
| Value(s)
| Yes
| No
|
1
| Was the Powertrain On-Board Diagnostic (OBD) System Check performed?
| --
|
Go to Step 2
| Go to Powertrain OBD System Check
|
2
| Perform the transmission fluid checking procedure. Refer to 4L60-E Transmission Fluid Checking Procedure.
Did you perform the fluid checking procedure?
| --
|
Go to Step 3
| Go to 4L60-E Transmission Fluid Checking Procedure
|
3
|
- Install the scan tool (tech 1)
®.
- Turn ON the ignition, with the engine OFF.
Important: Before clearing the DTCs, use the scan tool in order to record the Freeze
Frame and Failure Records. Using the Clear Info function erases the Freeze
Frame and Failure Records from the PCM.
- Record the Freeze Frame and Failure Records.
- Clear the DTCs.
- With the engine idling and at normal operating temperature, apply
the brake pedal.
- Select each transmission range: D1, D2, D3, D4, N, R and P.
Refer to Transmission Fluid Pressure (TFP) Manual Valve Position Switch
Logic.
Does each selected transmission range match the scan tool TFP switch A/B/C display?
| --
|
Go to Step 4
| Go to
Pressure Switch Assembly Resistance Check
|
4
|
- Install the scan tool.
- With the engine OFF, turn the ignition switch to the RUN position.
Important: Before clearing the DTCs, use the scan tool in order to record the Freeze
Frame and Failure Records for reference. The Clear Info function will erase
the data.
- Record the DTC Freeze Frame and Failure Records.
- Drive the vehicle in 4th gear with the TCC engaged.
Is the TCC Slip Speed greater than the specified value for 7 seconds?
| 130 RPM
|
Go to Step 5
| Go to Diagnostic Aids
|
5
|
- Inspect the Torque Converter Clutch Solenoid Valve (TCC Sol. Valve)
for the following conditions:
| • | Internal malfunction (such as sediment or damage) |
- Inspect the Torque Converter Clutch Pulse Width Modulation Solenoid
Valve (TCC PWM Sol. Valve) for the following conditions:
| • | Internal malfunction (such as sediment or damage) |
Did you find a problem?
| --
|
Go to Step 14
|
Go to Step 6
|
6
|
- Inspect the 1-2 Shift Solenoid Valve (1-2 SS Valve) for the following
conditions:
| • | Internal malfunction (such as sediment or damage) |
- Inspect the 2-3 Shift Solenoid Valve (2-3 SS Valve) for the following
conditions:
| • | Internal malfunction (such as sediment or damage) |
Did you find a problem?
| --
|
Go to Step 14
|
Go to Step 7
|
7
| Inspect the valve body assembly for a stuck TCC signal valve. Refer to Unit Repair.
Did you find a problem?
| --
|
Go to Step 14
|
Go to Step 8
|
8
| Inspect the torque converter assembly for the following conditions:
| • | Stator roller clutch not holding |
Did you find a problem?
| --
|
Go to Step 14
|
Go to Step 9
|
9
| Inspect the oil pump assembly for the following conditions:
| • | Stuck converter clutch valve |
| • | Converter clutch valve assembled backwards |
| • | Mispositioned converter clutch valve retaining ring |
| • | Mispositioned pump to case gasket |
| • | Restricted orifice cup plugs |
| • | Damaged orifice cup plugs |
| • | Over-tightened, or unevenly tightened pump body to cover bolts |
Refer to Unit Repair.
Did you find a problem?
| --
|
Go to Step 14
|
Go to Step 10
|
10
| Inspect the input housing and shaft assembly for the following conditions:
| • | Cut turbine shaft o-ring seal |
| • | Damaged turbine shaft o-ring seal |
| • | Restricted turbine shaft retainer and ball assembly |
| • | Damaged turbine shaft retainer and ball assembly |
Refer to Unit Repair.
Did you find a problem?
| --
|
Go to Step 14
|
Go to Step 11
|
11
| Inspect the 2-4 band assembly for the following conditions:
| • | The band anchor pin is not engaged. |
| • | Restricted apply passages in the 2-4 servo assembly |
| • | Blocked apply passages in the 2-4 servo assembly |
| • | Nicks or burrs on the servo pin |
| • | Nicks or burrs on the pin bore in the case |
| • | Damaged fourth servo piston |
| • | Misassembled fourth servo piston |
| • | Incorrect band apply pin |
| • | Damaged servo bore in the case |
| • | Porosity in the pistons |
| • | Damaged piston seal grooves |
| • | Plugged orifice cup plug |
| • | Missing orifice cup plug |
Refer to Unit Repair.
Did you find a problem?
| --
|
Go to Step 14
|
Go to Step 12
|
12
| Inspect the forward clutch assembly for the following conditions:
| • | Porosity in the forward clutch piston |
| • | Damaged forward clutch piston |
| • | Missing forward clutch piston inner and outer seals |
| • | Cut forward clutch piston inner and outer seals |
| • | Damaged forward clutch piston inner and outer seals |
| • | Missing input housing to forward clutch housing o-ring seal |
| • | Cut input housing to forward clutch housing o-ring seal |
| • | Damaged input housing to forward clutch housing o-ring seal |
| • | Damaged forward clutch housing |
| • | Damaged forward clutch housing retainer and ball assembly |
| • | Forward clutch housing retainer and ball assembly is not sealing. |
Refer to Unit Repair.
Did you find a problem?
| --
|
Go to Step 14
|
Go to Step 13
|
13
| Inspect the 3-4 clutch assembly for the following conditions:
| • | Porosity in the 3-4 clutch piston |
| • | Damaged 3-4 clutch piston |
| • | Missing 3-4 clutch inner and outer seals |
| • | Cut 3-4 clutch inner and outer seals |
| • | Damaged 3-4 clutch inner and outer seals |
| • | Damaged 3-4 clutch spring assembly |
| • | Damaged 3-4 clutch apply ring |
| • | Damaged piston seal grooves |
| • | Plugged orifice cup plug |
| • | Missing orifice cup plug |
Refer to Unit Repair.
Did you find a problem?
| --
|
Go to Step 14
| Go to Diagnostic Aids
|
14
| In order to verify your repair, perform the following procedure:
- Select DTC.
- Select Clear Info.
- Operate the vehicle under the following conditions:
| • | Drive the vehicle in D4, with the TCC ON, and a throttle position
of 9-35%. |
| • | Ensure that the TCC Slip Speed is -20 to +20 RPM
for at least 12 seconds. |
- Select Specific DTC. Enter DTC P1870.
Has the test run and passed?
| --
| System OK
| Begin the diagnosis again. Go to Step 1
|
