Before Pinpoint Tests
Before Pinpoint TestsNOTE: Prior to entering pinpoint tests, check the PCM wiring harness for proper connections, bent or broken pins, corrosion, loose wires, proper routing, proper seals and their condition. Check the powertrain control module, sensors and actuators for damage. Refer to Computers and Control Systems.
If DTCs appear while performing the on-board diagnostics refer to the On-Board Diagnostic Trouble Code Description Chart for the appropriate service procedure. Diagnostic Trouble Code Tests and Associated Procedures Prior to entering pinpoint tests, refer to any TSBs and OASIS messages for 4R70W transmission concerns.
NOTE: Prior to entering pinpoint tests, the vehicle harness must be checked for continuity and shorts; the powertrain control module (PCM)(12A650) must be checked for any concerns.
NOTE: If any non-transmission DTCs appear, service those codes first. They could affect the electrical operation of the transmission. Record and erase DTCs from continuous memory after service has been performed. After servicing any DTCs in the Quick Test, repeat the Quick Test.
Rotunda Transmission Tester
NOTE: Use the AODE transmission tester overlay to diagnose the 4R70W transmission.
Use Rotunda Transmission Tester 007-0085D or equivalent to diagnose electronically controlled transmissions. The following instructions outline the set up and use of this tester in the pinpoint tests for the 4R70W.
Transmission Tester:
Overlays and Adapters
When overlay and cable are correctly installed, only LEDs with the (0) symbol will light when the overlay symbol and cable correctly match.
Tester Jacks
1. VPWR pin jacks (red): VPWR test points for solenoid circuits.
NOTE: The tester overlay is labeled for the MCCC solenoid. This is used to test the torque converter clutch (TCC) solenoid.
2. Solenoid (MCCC, EPC) signal line pin jacks (black): Signal line test points for solenoid circuits.
3. BAT+ (red) and BAT- (black) pin jacks: Battery reference points when measuring circuits for shorts.
4. TOT pin jacks: Test points for transmission fluid temperature (TFT) sensor.
5. OSS Pin Jacks: Test points for output speed shaft sensor (055).
LEDs and Controls
1. Status LEDs: LED is off when not activated by tester (solenoid not activated, open circuit or signal line short to ground). LED is green when activated by tester and current draw is correct. LED is red when activated by tester and current draw is excessive (short to battery positive [B+] voltage). All LEDs are orange during Selftest.
2. Solenoid Activate Buttons: Energize respective solenoids during click testing and activate selected circuits during drive mode testing.
3. Bench/Drive Switch: Selects operating mode, either BENCH or DRIVE.
4. Solenoid Select/Gear Select Switch: Has three functions:
- BENCH mode: acts as shift solenoid selector for click testing
- DRIVE mode: acts as forward gear selector in place of vehicle PCM controlled shifting. Hydraulic safety mechanisms and overrides are built into the transmission
- OHMS CHECK: allows you to measure resistance (ohms)
Instructions
The Rotunda Transmission Tester 067-085D or equivalent allows the operation of the electrical portion of the transmission independent of the vehicle electronics to determine transmission concerns.
The transmission tester usage is divided into six steps:
1. Preliminary inspections
2. Installation procedures
3. Static testing - engine oft
4. Dynamic testing engine on
5. Transmission range (TR) sensor testing
6. Disconnecting the tester
Preliminary Inspections
Before any diagnostic testing is done on the vehicle, some preliminary checks must be performed. Be sure to write down any results, especially any DTCs found, for future reference.
1. Check transmission fluid level and condition.
2. Check for add-on items (phone, computer, CB radio, etc.).
3. Visually inspect wiring harness and connectors.
4. Check for vehicle modifications.
5. Check shift linkage for proper adjustment.
6. Verify customer's concern:
- Upshift
- Downshift
- Coasting
- Engagement
- Noise/Vibration
7. Vehicle must be at normal operating temperature.
8. Perform vehicle on-board diagnostic.
9. Record all DTCs.
10. Service all non4ransmission codes first. Installation Procedures
Installing the transmission tester at the transmission connector allows separation of the vehicle electronics from transmission electronics. Disconnecting normal vehicle electronics will set additional DTCs and cause firm shifts. (Disconnecting the transmission connector defaults transmission to maximum line pressure).
NOTE: During tester usage additional DTCs may be set. Therefore, it is important that all DTCs are erased after service has been made. To verify elimination of all DTCs rerun On-Board Diagnostic.
NOTE: The following manuals should be available to assist in diagnosis of electronically controlled transmissions:
- Powertrain Control/Emissions Diagnosis Manual8
- Transmission Tester Manual (provided with tester)
CAUTION: Do not attempt to pry off connectors with a screwdriver. This will damage the connector and could result in transmission concerns.
1. Disconnect vehicle wiring harness at transmission connector.
2. Turn tester solenoid select switch to the OHMS CHECK position.
CAUTION: Route all cables away from heat sources.
3. Connect appropriate tester interface cable and overlay to transmission and tester.
CAUTION: Route gauge line away from heat sources.
4. Install a line pressure gauge into line pressure tap on transmission.
5. Plug transmission tester power supply into cigar lighter receptacle. At this time, all LEDs should illuminate for a short period and then turn off. This is the tester internal circuit check.
6. Position BENCH / DRIVE switch to BENCH mode.
Static Testing - Engine Off
Static testing procedures allow shop testing of the transmission in the vehicle or on the bench. Completion of these tests prove out transmission electronics.
CAUTION: For resistance checks, be sure the tester solenoid select switch Is set to the OHMS/CHECK position or damage to the ohmmeter may result.
- Refer to the appropriate pinpoint test for the DTCs displayed.
- Use a Rotunda 73 Digital Multimeter 105-ROO51 and the transmission tester to perform the pinpoint tests as indicated by DTCs displayed.
- Service as indicated by the pinpoint tests. Always retest and road test vehicle after service.
Resistance/Continuity Tests - EPC Solenoid
1. Set multimeter to 100-200 ohm range.
2. Connect negative lead of multimeter to the EPC jack.
3. Connect positive lead of multimeter to the VPWR jack.
4. Record resistance.
5. Compare results to the following charts for values.
6. If out of specification, refer to Pinpoint Test E in this section. E: Electronic Pressure Control (EPC) Solenoid
Resistance/Continuity Tests - Solenoids (SS1, SS2, TCC)
1. Set multimeter to 100-200 ohm range.
2. Connect positive lead of multimeter to the appropriate VPWR jack for the solenoid being tested.
3. Connect negative lead of the multimeter to the appropriate solenoid (SS1, 882, MCCC) jack and record resistance.
Solenoid Resistance Chart:
4. Compare results to the chart for values.
5. If out of specification, refer to Pinpoint Test A (881, 882) or Pinpoint Test C (TCC).
Resistance/Continuity Tests - Transmission Fluid Temperature (TFT) Sensor
1. Set multimeter to 1000 ohm scale.
2. Connect multimeter positive lead to TOT+ jack.
3. Connect multimeter negative lead to TOT- jack.
4. Record resistance. Resistance will vary with temperature.
5. Compare results to the chart.
Solenoid Resistance Affected By Temperature:
6. If out of specification, refer to Pinpoint Test B in this section.
Resistance/Continuity Tests Output Shaft Speed (OSS) Sensor
1. Set multimeter to 1000 ohm scale.
2. Connect the positive lead of the multimeter to the (+)OSS.
3. Connect the negative lead of the multimeter to the (-)OSS.
4. Record resistance.
5. OSS should be 450-750 ohms. If out of specification, refer to Pinpoint Test F in this section.
Solenoid Voltage Test
1. Slide MODE switch to BENCH position.
2. Set multimeter to 20 volt DC range.
Tester Mode Settings:
3. Select one solenoid to test and connect the multimeter leads as follows:
- If testing 881, 882 or 883 solenoid, turn the SOLENOID SELECT dial to SS1, SS2 or SS3 before hooking up leads.
- If testing EPC or TCC continue.
- Connect negative lead to the appropriate solenoid jack.
- Connect positive lead to the appropriate VPWR jack.
4. Press the solenoid's ACTIVATE/DEACTIVATE button and check voltage.
The LED should light, the voltage should change and an audible click may be heard. Refer to LEDs and Controls to interpret LED status.
5. Observe and record values. LED Status:
- LED turns green when solenoid activates and off when deactivated.
- LED turns red if an activated solenoid I harness is shorted to B+.
- LED remains off if an activated solenoid/harness is shorted to ground or no continuity.
Dynamic Testing - Engine On
Dynamic testing allows the transmission to be proven out electronically and hydraulically.
Preliminary Set Up
1. Set BENCH/DRIVE switch to DRIVE mode.
2. Set gear select switch to first gear position.
3. Place vehicle in PARK (P).
4. Start engine.
EPC Solenoid
CAUTION: Do not attempt to hold the EPC Switch depressed (minimum line pressure) and stall the transmission (holding the vehicle with the brake while depressing the throttle with the transmission in gear), as transmission damage will result.
1. Observe line pressure. Record value.
Line pressure should go to maximum. If not, refer to the Diagnosis by Symptom routines for diagnostic tips or Pinpoint Test E concerning EPC solenoid.
2. Press EPC switch. Line pressure should drop to a minimum value. Record value. If not, refer to the Diagnosis by Symptom routines or Pinpoint Test E for the EPC solenoid.
Transmission Engagements
1. Verify that MODE switch is in DRIVE mode.
2. Turn GEAR SELECT dial to 1.
3. Start engine.
4. Shift vehicle from PARK (P) to REVERSE (R).
- Did vehicle shift into REVERSE (R)?
- Was engagement firm?
5. Depress EPC switch. Line pressure should drop to idle pressure.
While holding EPC switch down, shift vehicle from PARK (P) to REVERSE (R).
- Did vehicle shift into REVERSE (R)?
- Was engagement smooth?
- Shift vehicle from REVERSE (R) to PARK (P).
- Release EPC switch. Line pressure should rise to maximum pressure.
6. Shift vehicle from PARK (P) to DRIVE (D).
- Did vehicle shift into DRIVE (D)?
- Was engagement firm?
7. Shift vehicle from DRIVE (D) to PARK (P).
8. Depress EPC switch. Pressure should drop to idle pressure.
9. Depress EPC switch. Line pressure should drop to idle pressure. While holding EPC switch down, shift vehicle from PARK (P) to DRIVE (D).
- Did the vehicle shift from PARK (P) to DRIVE (D)?
- Was the engagement smooth?
10. Release EPC switch.
Upshifts/Downshifts
NOTE: Upshifts and downshifts will be firm during this procedure.
NOTE: Pressure gauges may be removed.
NOTE: These tests should be performed on the road. If performed on the hoist, feeling the shifts engage may not be possible.
LEDs will turn green when solenoids are activated and turn off when deactivated. Refer to the appropriate overlay for the proper status shift sequence of the shift solenoids (7G484) during upshifts and downshifts.
1. Shift vehicle into OVERDRIVE and accelerate to 24km/h (15mph). Select second gear by rotating gear select switch to second gear position.
- Did vehicle upshift to second gear?
- Did appropriate shift solenoids activate or deactivate?
2. Accelerate to 40 km/h (25 mph) and select third gear position.
- Did vehicle upshift to third gear?
- Did appropriate shift solenoids activate or deactivate?
3. Accelerate to 56-72 km/h (35-45 mph) and select fourth gear position.
- Did vehicle upshift to fourth gear?
- Did appropriate shift solenoids activate or deactivate?
4. Reverse the order to downshift.
- Does vehicle downshift from fourth to third, third to second, and second to first?
- Did appropriate shift solenoids activate or deactivate?
Torque Converter Clutch (TCC) Engagement
CAUTION: Do not depress MCCC switch with transmission in gear and the vehicle at a stop. Damage to the torque converter clutch may result.
NOTE: This test should be performed on the road. If performed on a hoist, feeling the torque converter clutch engage may not be possible.
1. Accelerate and shift vehicle into third gear. Hold speed steady and press the MCCC switch.
2. Check for the following conditions:
- Does the torque converter engage?
- Does the engine rpm drop?
- Did torque converter clutch solenoid (TCC solenoid)(7G 136) activate?
Output Shaft Speed (OSS) Sensor
NOTE: This test may be performed on the hoist or on the road.
1. Set multimeter to 20 volts AC.
2. Connect multimeter positive lead to the OSS (+) jack.
3. Connect multimeter negative lead to the OSS (-) jack.
4. Slowly accelerate vehicle and monitor multimeter. Does voltage increase with vehicle speed?
5. If testing of the TR/MLP sensor is not required refer to disconnecting the tester in this section. If TR/MLP sensor testing is required, continue.
Transmission Range (TR) Sensor Testing
Transmission Range (TR) Sensor Testing:
Introduction
The transmission tester operates the electrical portion of the transmission range (TR) sensor. The TR sensor tester usage is divided into five steps:
1. Preliminary Testing and Diagnosis
2. Transmission Tester Installation (Set-Up Procedure)
3. Testing TR Sensor
4. Voltage Tests - Park/Neutral, Backup Lamp and Optional Circuits
5. Disconnecting the tester
Preliminary Testing and Diagnosis
Before any diagnostic testing is performed on a vehicle, some preliminary checks must be completed. Be sure to write down any results, especially any DTCs, for future reference.
- Check transmission fluid level and condition.
- Check for add-on items (phone, computer, CB radio, etc).
- Visually inspect wiring harness and connectors.
- Check for vehicle modifications.
- Verify that the shift linkage is properly adjusted in OVERDRIVE.
- Verify that TR sensor is properly adjusted in NEUTRAL (N).
- Verify customer concern:
a. Upshift
b. Downshift
c. Coasting
d. Engagement
e. Noise/Vibration
- Vehicle must be at a normal operating temperature.
- Perform vehicle On-Board Diagnostic.
- Record all DTCs.
- Service all non4ransmission DTCs first.
Installation Procedures
NOTE: During tester usage additional DTCs may be set. Therefore, it is important that all codes are erased after service has been made. To verify elimination of all DTCs, rerun On-Board Diagnostic.
Installing the Rotunda Transmission Tester 007-0085D at the TR Sensor connector separates the vehicle electronics from the TR sensor electronics.
CAUTION: Do not attempt to pry off connectors with a screwdriver. This will damage the connector and could result In a transmission concern.
1. Disconnect vehicle harness at TR sensor connector.
CAUTION: Route all cables away from heat sources.
NOTE: For in-vehicle testing, use the transmission tester extension cable.
Tester Cable Application Chart:
2. Set BENCH/DRIVE switch to DRIVE mode. Install TR Sensor Overlay onto tester. Connect interface cable to transmission tester and then to the TR sensor connector. Refer to chart for the proper cable/application.
3. Turn test select switch to the TR SENSOR TEST position.
4. Plug transmission tester power supply plug into cigar lighter.
At this time, all LEDs should illuminate for a short period and then turn off. This is the tester internal circuit check.
Resistance/Continuity Tests
Static testing procedures allow for shop testing of the transmission in the vehicle or on the bench. Completion of these tests prove out the TR sensor electronically.
CAUTION: For resistance checks, be sure that the tester selector switch Is set to the TR SENSOR TEST position or damage to the multimeter may result.
- Use multimeter and the Rotunda Transmission Tester 007-0085D to perform Pinpoint Test D based on the DTCs displayed.
- Perform services as directed by the pinpoint tests. Always retest and road test vehicle after any service.
1. Set multimeter to 1000 ohm range.
2. Connect the positive lead of the multimeter to the TR / MLP jack.
3. Connect the negative lead of the multimeter to the SIG RTN jack.
4. Move transmission range (TR) selector lever into each gear position.
5. Record resistance at each position.
Transmission Range (TR) Sensor Resistance Chart:
6. Compare resistance to the chart. If out of range, refer to Pinpoint Test D.
Voltage Tests - Park/Neutral, Backup Lamp and Optional Circuits
NOTE: LED will turn red when the circuit closes and turn off when the circuit is open.
1. Move tester select switch to the TR/MLP SENSOR TEST position.
2. Press and hold each button while moving the transmission range selector lever through each range.
3. Monitor each LED.
4. The status LED should indicate red only in the indicated position. Refer to overlay.
5. If the LED does not indicate red in the desired position, or indicates red in another position, first verify TR alignment and then retest. If the sensor fails, replace.
Disconnecting the Tester
CAUTION: Do not attempt to pry off connectors with a screwdriver. This will damage the connector and could result in a transmission concern.
1. Disconnect transmission tester from the TR sensor connector.
2. Reinstall vehicle wiring harness. Verify secure connection by pulling up on the harness.
3. Disconnect transmission tester power lead from vehicle.
4. Erase all DTCs.
5. Rerun On-Board Diagnostic tests to receive a pass code.
6. Verify that the customer concern has been eliminated.