SERVICE MANUAL UPDATE-SEC. 7 HYDRA-MATICAUTO TRANS DIAG.
SUBJECT: HYDRA-MATIC 4L60 AUTOMATIC TRANSMISSION DIAGNOSIS
MODEL and YEAR: 1993 C/K, S/T TRUCKS AND M/L, GVANS
TRANSMISSION APPLICATIONS:
1993 HYDRA-MATIC 4L60-E (M30)
TRANSMISSION MODELS:
ALL
SUBJECT:
1993 SECTION 7 HYDRA-MATIC 4L60-E AUTOMATIC TRANSMISSION DIAGNOSIS MANUAL UPDATE
VEHICLE APPLICATIONS:
C/K - TRUCKS UNDER 8600 GVW S/T - TRUCKS WITH 4.3L M/L AND G VANS
BULLETIN COVERS:
New Product Information for 1993 HYDRA-MATIC 4L60-E transmissions. This information has been updated since publication of the 1993 Service Manual and should be noted accordingly. Be certain to familiarize yourself with these updates to properly diagnose the HYDRA-MATIC 4L60-E transmission.
DATE OF PRODUCTION CHANGE:
Beginning with Start of Production 1993, HYDRA-MATIC 4L60-E transmissions were built with the product changes explained in this bulletin.
SERVICE MANUAL REFERENCE:
Figures 1 and 2 update the charts located in the Transmission Diagnosis Section of the 1993 Service Manuals. Figures 3-6 are charts that can be added to enhance the 1993 Service Manual Section 7A-14A.
TECH 1 PARAMETER IN PARK AT IDLE UPSHIFTS IN UPSHIFTS IN D4 OR D3 D2 OR Dl
ENGINE SPEED 550-750 Varies Varies TRANS OUTPUT SPEED 0 (1) Varies Varies VEHICLE SPEED 0 Varies Varies KICKDOWN ENABLED NO NO NO A/B/C RNG OFF ON OFF OFF ON ON or OFF OFF OFF OFF OFF ON or ON OFF OFF PRNDLE SELECT Park/Neutral Drive 4 or D3 D2 or Dl COMMANDED TCC OFF (5) OFF TCC SLIP RPM 600-750 +/-30 If Applied 0-2500 RPM COMMANDED GEAR 1 1, 2, 3, or 4 1 or 2 (4) 1-2 SOL / 2-3 SOL ON ON ON ON or OFF ON ON ON or or OFF OFF or ON OFF OFF ON DESIRED PCS 1.01 0 - 1.01 0 - 1.01 ACTUALPCS 1.01 0 - 1.01 0 - 1.01 PCS DUTY CYCLE 40 - 60% 0 - 70 % 0 - 70 % BRAKE SWITCH Released Released Released 4WD LOW SWITCH OFF OFF OFF ENG COOL TEMP 85 C - 105 C (8) 85 C - 105 C (8) 85 C - 105 C (8) TRANS FLUID TEMP 30 C - 130 C (8) 30 C - 130 C (8) 30 C - 130 C THROTTLE ANGLE 0% 10 - 50% 10 - 50% THROTTLE POSITION .4 -.6 V .6 - 2.5 V .6 - 2.5 V 1-2 SHIFT TIME .3 - 1.35 .3 - 1.25 .3 - 1.25 Sec.(2)(3) Sec. (2)(3) Sec. (2)(3) ADAPTABLE SHIFT No (3) YES NO 1-2 SHIFT ERROR 0 - 6.25 0 - 6.25 0 - 6.25 Sec. (2)(3) Sec. (2)(3) Sec. (2)(3) 2-3 SHIFT TIME .3 - 1.35 .3 - 1.25 .3 - 1.25 Sec. (2)(3) Sec. (2)(3) Sec. (2)(3) 1-2 ADAPT CELL 1 -5 -10 -5 -10 -5 -10 1-2 ADAPT CELL 2 -5 -10 -5 -10 -5 -10 1-2 ADAPT CELL 3 -5 -10 -5 -10 -5 -10 A/C REQUEST OFF OFF OFF C/C STATUS OFF OFF OFF CALIBRATION ID Internal ID Only Internal ID Only Internal ID Only SYSTEM VOLTS 13.6 13.6 13.6 CTR FDBK 1/2 2/3 ON ON (6) ON ON or OFF ON ON ON or OFF ON (6) or OFF OFF or ON OFF (6)
CONT FDBK TCC OFF (6) OFF ON (6) OFF (6) 3-2 CONTROL SOL 0% 90% Above 1st Gear 90% Above 1st Gear 3-2 CONTROL FDBK OFF Oscillates ON/OFF Oscillates ON/OFF
1. There may be a small speed reading due to vehicle vibration.
2. Zero until a shift occurs.
3. 'Yes' means the shift time is an accurate and valid number. (If shift was adaptable.) If shift was adaptable, 'No' indicates the shift time is not accurate for one or more of the following reasons:
o Transmission is in D2 or D1
o There is a long shift delay
o There is a long shift time
o There has been a significant throttle angle change
o Transmission is in hot mode
o A shift starts too soon after the solenoids change states
o Diagnostic codes are set (21, 22, 24, 28, 53, 58, 59, 72, 73, 75, 79, 81 or 82)
o There has been a significant vehicle speed change
o 4WD lo switch is on
4. PCM will command first gear only if THROTTLE ANGLE is 100%.
5. TCC normally applies in fourth gear but may apply in D4 third gear at 100% THROTTLE ANGLE at 75 mph. It will apply earlier in D3 third gear.
6. Should match commanded solenoid state.
7. Value will drop during a 3-2 downshift.
8. Normal operating temperature.
Figure 2 - Typical TECH 1 Data Values
TRANSMISSION ELECTRICAL CONNECTOR
The transmission electrical connector is a very important part of the HYDRA-MATIC 4L60-E operating system. Anything that interferes with the electrical connection can cause the transmission to set Diagnostic Trouble Codes and/or operate incorrectly.
The following items can affect the electrical connection:
- Bent pins in the connector from rough handling during connection and disconnection
- Wires backing away from the pins or coming uncrimped (in either the transmission or vehicle wiring harness)
- Dirt contamination entering the connector when it is unconnected
- Pins in the connector backing out of the connector or pushed out during connection
- Excessive transmission fluid leaking into the connector, wicking up into the vehicle wiring harness and degrading the wire insulation*
- Water/moisture intrusion in the connector
- Low pin retention from excessive connection and disconnection of the wiring harness
- Pin corrosion from contamination
*The presence of transmission fluid in the transmission connector is not harmful in itself. The fluid only affects the vehicle harness wiring insulation if the fluid wicks up that far.
Points to remember when working with the transmission electrical connector:
- To remove the connector, squeeze the two tabs towards each other and pull straight up (See illustration).
- Carefully limit twisting or wiggling the connector during removal. This can bend pins.
- DO NOT pry the connector off with a screwdriver or other tool.
- To install the connector, first orient the pins by lining up the arrows on each half of the connector. Push the connector straight down into the transmission without twisting or angling the mating parts.
- The connector should click into place with a positive feel and/or noise.
- Whenever the transmission pass-thru connector is disconnected from the vehicle harness and the engine is running, multiple Diagnostic Trouble Codes will set. Be sure to clear these codes after re-connecting the pass-thru connector.
DTC's 59, 67 and 82 will set with key on, engine off.
DTC's 59, 66, 67, 73 and 82 will set with key on, engine on.
4L60-E COMPONENT RESISTANCE CHART
COMPONENT TERMINAL WIRE PASS-THRU RESISTANCE CKT# COLOR PIN @ 20 degrees C
A RED E * 1149B 1-2 SHIFT SOLENOID 20 - 40 Ohms B GRN LT A * 1222
A RED E * 1149A 2-3 SHIFT SOLENOID 20 - 40 Ohms B YEL B * 1223
A RED E * 1149C 3-2 CONTROL SOLENOID 9 - 14 Ohms B WHT S 897
A PPL C 1228 PRESSURE CONTROL SOLENOID 3.5 - 8 Ohms B BLU LT D 1229 TRANS TEMPERATURE SENSOR A BRN L 1227 2.9 - 4.0 Ohms B GRA M 455 see PSA chart Figure 18 C PNK N 1224
PRESSURE SWITCH ASSEMBLY D ORN P 1226
E BLUE DK R 1225
A RED E * 1149E TCC SOLENOID 20 - 40 Ohms B BLACK T 422A
*Spliced internally to Pin E.
General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.
