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LOCATION:    2.3 Electronic Automatic Transmission Control (ETC)   >   13 Diagnosis - Complaint Related Diagnostic Chart - Overall Function


Diagnosis - Complaint Related Diagnostic Chart - Overall Function

Complaint/Problem Possible cause Test step/Remedy 1)
-- Engine quits after selecting a drive gear and noise from transmission in position "N" or "P" (no DTC's are stored in DTC memory) 1. PWM solenoid valve (Y3/6y6) (torque converter lock-up) locked-up, (due to foreign matter).
2. Torque converter lock-up clutch control valve (22) locked up, (due to foreign matter).
(applies up to transmission number 22890 only, thereafter screen installed in oil passage).
1. Replace PWM solenoid valve (Y3/6y6).
2. Clean out torque converter lock-up clutch control valve.
-- Rumbling, droning or possible shuttering with torque converter lock-up. Insuffient torque converter slippage rpm Using the HHT, turn off the torque converter lock-up.
If the complaint can not be duplicated thereafter replace the PWM solenoid valve (Y3/6y6) and reset the adaption values, using the HHT.
-- Howling, whistle noises at
(> 4000rpm) in all gears.
Transmission ATF filter clogged.
Transmission AFT oil pump
Replace ATF oil filter.
Replace ATF oil pump.
-- Howling, singing noises Gear set noises: 1st, 2nd, 5th gears


Sealing ring at propeller shaft intermediate bearing is touching bearing inner race.
Currently no solution, please contact regional office and advise of VIN and mileage.

Replace propeller shaft intermediate bearing with bearing that uses a black colored seal.
-- Load reversal noise (cracking noise) Shear noise between output flange and collar nut.


Up to transmission number 30332, there after collared nut and tightening torque value changed, see Remedy.
Use collar nut with Dacromet coating (silver color).
(Tightening torque: 200Nm)
-- Ticking noises from center console shift gate while driving at slow speeds. Loose connection at R/P lock valve (Y66/1) connector. Check and or replace R/P lock valve (Y66/1) connector.
-- Harsh 2 1 deceleration downshift Transmission adaption (adaption of ETC).
ETC software date
Free-wheeling unit (F1)
See 11/36,
See 13/7
-- Harsh 3 2 deceleration downshift
(reappears also after preforming transmission adaption.
Clutch K3


Applies to all models with engine 119, 120 up to transmission number 27083
See 13/8
-- No or late upshift of transmission Different size tires mounted on the front axle.
Wrong factor attained shortly after starting to drive.
Mount proper size tires on front axle.
-- No upshift from 3 4 and 4 5 when releasing accelerator pedal quickly, only works if transmission is in "S" program. Upshift prevention due to dynamic-sporty driving style of client. Educate/advise client.
-- No upshift into 5th gear with WOT or kick-down. The upshift 4 5 occurs with WOT or kick-down if the rev-limiter rpm is reached. High power vehicles will shift into 5th gear only when attaining the rev-limiter rpm (250 km) in 5th gear. Educate/advise client.
-- No upshift out of 1st gear (program "S" selected) and out of 2nd gear (program "W" selected) at 1,500 rpm with engine "cold". Fault can not be duplicated every time. Transmission range recognition switch (S16/10) and/or Electronic Transmission Control (ETC). Remove parts and contact regional office.
-- Engine revs up during 2 3 shift and /or has harsh downshift during 3 2 shift. ATF level in transmission
AFT oil filter

Free-wheeling unit (F2)


Check ATF level in transmission or fill to correct level.
See 13/8
See document AR27.00-P-0101A
-- Shudder in 2 3 power upshift or 3 2 downshift (engine braking) ATF level in transmission
AFT oil filter
Command or Regulating, Shift Control Valves
Clutch K3


Check ATF level in transmission or fill to correct level.
See 13/9
See document AR27.00-P-0101A
-- No downshift via kick-down function Required pedal value < 95%
(Test using HHT)


All models with engine 111
Check engine management, if necessary readjust,
see DM Engines.
-- Delayed engagement/no transmission of power in "R" and/or "D", at times intermittent. Possible causes regarding intermittent complaints:
ATF oil level in transmission.


Check ATF level in transmission or fill to correct level.

Transmission range recognition switch (S16/10)
ATF oil filter


Disassemble/check center console shift gate

Delayed pressure build-up at piston B2/B3

Allocation of ETC/Electro-hydraulic control unit (EHS)
See 13/10




See document AR27.00-P-0101A






See document AR27.60-P-0920B


-- Delayed engagement/no transmission of power with gear selector lever in "R" and/or "D", at times intermittent. Possible causes regarding duplicatable complaints:


Collared nut loose.
Brake B2/B3.


Remove and replace: Brake B2, Brake B3, and parking lock wheel

Disassemble and reassemble Brake B2


Shift pressure regulating solenoid valve (Y3/6y2).
Modulating pressure regulating solenoid
valve (Y3/6y1).
Command or Regulating, Shift control valves.
Transmission circlips









See document AR27.50-P-0781A


See document AR27.50-P-0880A
-- Harsh coasting downshift 4 3, just before vehicle comes to a stop. Separator plate in the Electro-hydraulic control unit


Occurs only with gear selector lever in "D" or 4th gear, not if gear selector lever is in: 3rd or 2nd gear. Applies up to transmission number 0527574, thereafter a modified separator plate was introduced into production.
Replace separator plate, P/N 140 277 39 14
-- Harsh 2 1 coasting downshift
ETC software version


Software versions optimised as of April 15, 1998

Free-wheeling unit (F1) faulty


Since it is possible that the free-wheeling unit F2 will be damaged as well, replace F2 (P/N 140 270 05 31) the hollow shaft, rear sun gear/clutch K3 as well.
Replace ETC software version




Replace Free-wheeling unit (F1)
-- Harsh 3 2 coasting downshift
(occurs after transmission adaption process as well)
Clutch K3 runs empty


Applies to all models using engine 119, 120 up to transmission number 27083, thereafter electro-hydraulic control unit optimised.

Disc spring for piston in Clutch K3 is missing.
Install ETC repair set, P/N 140 540 08 45






Install missing disc spring for piston in Clutch K3
-- Engine revs up during 2 3 shift and /or has harsh downshift during 3 2 shift. ATF oil filter not installed.


Free-wheeling unit F2 faulty
Install missing ATF oil filter.


Replace F2 (P/N 140 270 05 31) the hollow shaft, rear sun gear/clutch K3.


Applies up to transmission number 981435 only.
P/N 140 270 05 31 applies to W5A330 and W5A580 only.
-- Shudder in 2 3 power upshift or 3 2 downshift (engine braking) ATF oil filter not installed.

Command or Regulating, Shift Control Valves stuck due to foreign matter

Clutch plates of clutch K3 are either burnt, have hot-spots or are worn down.
Install missing ATF oil filter.

Check valves for full travel and ease of movement, if necessary free up valves as needed.

Replace inner and outer clutch plates of clutch K3.


Applies up to transmission number 331159 only, thereafter the thickness of the clutch plates changed.
Additionally replace torque converter lock-up clutch control valve (22).


Applies up to transmission number 221668 only.
-- Delayed engagement/no transmission of power with gear selector lever in "R" and/or "D"

Note:
Possible causes where fault CAN NOT be reproduced each time.
Transmission range recognition switch (S16/10)







ATF oil filter not installed.

Older engagement process, therefore delayed pressure build up at piston B2 and B3






False allocation ETC/Electo-hydraulic control unit.
Replace the Transmission range recognition switch (S16/10), only if upon testing with the HHT, the HHT display shows "Between Selections" or "Fault".


A fault code for the above is no longer set in memory as of software version e03/f08

Install ATF oil filter.

New engagement process (replace ETC, electro-hydraulic control unit, use repair set)


Applies only up to transmission number 23104 with software: e00, e01, f04, f06, r00, thereafter the piston B2 was optimized.

Determine proper allocation (swap ETC or Electro-hydraulic control unit).


Applies up to 07.96 only, there after allocation changed in production.
-- Delayed engagement/no transmission of power with gear selector lever in "R" and/or "D"

Note:
Possible causes where fault
CAN BE reproduced each time.
Torx screws (M8X60) loose or missing for piston guide on piston B2/B3

Shift pressure regulating solenoid valve (Y3/6y2), stuck due to foreign matter.

Modulating pressure regulating solenoid
valve (Y3/6y1), stuck due to foreign matter.





Command or Regulating, Shift Control Valves stuck due to foreign matter.

Seal rings for piston B2 or B3 damaged.

Circlip for disc spring for piston B2/B3 is not installed in groove.
Tighten loose torx screws or replace missing torx screws.



Replace (Y3/6y2)


Replace (Y3/6y1)


Applies up to transmission number 538312 only, thereafter screen installed in oil passage.

Check valves for full travel and ease of movement, if necessary free up valves as needed.

Replace seal rings.

Replace transmission, flush transmission oil cooler and all lines. Replace torque converter only if upon flushing there are metal shavings present.
-- Continued from 13/11 Circlip for output shaft ball bearing is missing or not in the groove.


Circlip for outer disc spring for Brake B3 is not in the groove.


Circlip for rear planetary sun gear shaft is missing or not in the groove.
Replace transmission, flush transmission oil cooler and all lines. Replace torque converter only if upon flushing there are metal shavings present.

Replace transmission, flush transmission oil cooler and all lines. Replace torque converter only if upon flushing there are metal shavings present.

Replace transmission, flush transmission oil cooler and all lines. Replace torque converter only if upon flushing there are metal shavings present.
-- ATF oil leak near electro-hydraulic control unit connector Electro-hydraulic control unit connector
Electrical conductor plate of electro-hydraulic control unit
Electro-hydraulic control unit O-rings
See 13/13
-- ATF oil leaks near torque converter housing Transmission over filled with ATF
(ATF is escaping via transmission breather hole)
Outer brake carrier B1
Torque converter
ATF oil pump
See 13/15
Check ATF fluid level, fill up as necessary,
see document AF27.00-P-0101A
-- ATF oil leak near electro-hydraulic control unit connector


Prior to starting any repairs, check the ATF fluid level.
Distorted O-rings





Distorted connector





The electrical conductor plate is not resting properly on the valve body housing. Therefore, the connector is not properly centered in the bore of the support plate and does not seal completely around its circumference.





Electrical connections at the electrical conductor plate are leaking ATF. Therefore, ATF leaks into in harness, at times to ETC control module (N15/3).
Replace O-rings


Applies up to transmission number 1211278 only, thereafter modified material used (color: red/brown).

Replace connector.


Applies up to transmission number 1309692 only, thereafter modified material used.

Carefully remove boss on the electrical conductor plate
(Figure 1, next page, arrow), to allow proper seating.


Applies only between 09/97 and 02/98, up to transmission number 77692 only.




Replace the following components:
electrical conductor plate, connector and O-rings.
1) Observe Preparation for Test, see 22.

Valve unit (Y3/6)
(sectional, as seen from below)
(arrow, remove boss in electrical conductor plate)

















Figure 1
  P27.19-2024-11

Complaint/Problem Possible cause Test step/Remedy1)
-- ATF oil leaks near torque converter


Prior to starting any repairs, check the ATF fluid level.
Outer brake carrier B1 mounting screws (Torx M6)






Lower 6 mounting screws on torque converter housing.

Torque converter leaks at its welding seam.

Radial sealing ring of ATF oil pump damaged.

O-ring for ATF oil pump damaged/missing.
Clean out mount screw (Torx) threads and reinstall mount screws with Locktite 574 (P/N 001 989 89 20).


Applies up to transmission number 981619, thereafter coated mount screws used in production.

Clean out mount screw threads and reinstall mount screws with Locktite 574 (P/N 001 989 89 20).

Replace torque converter.

Replace radial seal ring.

Replace O-ring.





Transmission is in electrical limp-home-mode Solenoid valves
Harness is damaged from ETC control module to each individual solenoid valve.
End stage fault in ETC control module
See 13/20 as well.
Transmission is in electrical limp-home-mode Harness is damaged from ETC control module to each RPM sensor.
RPM sensors are faulty
See 13/21 as well.
Transmission is in electrical limp-home-mode Harness is damaged from ETC control module to each RPM sensor.
RPM sensors are faulty.
Vehicles with less than 600 miles:
Impulse wheel window misaligned, due to manufacture, loose or axially misaligned.
See 13/21 as well.




Replace clutch K1
Transmission does not transmit engine power. Harness is damaged from ETC control module to each RPM sensor.
RPM sensors are faulty.
See 13/21 as well.
-- Transmission gear selector lever in "Between Selections", transmission is in electrical limp-home-mode
Applies to all models without "Touch Shift" feature.
Shift linkage, Transmission range recognition switch (S16/10)
See 13/22 as well,
-- Engine starts with a delay Shift linkage adjusted incorrectly.
Plunger of starter lock-out is stuck.
Adjust shift linkage.
Replace electrical conductor plate
--
--
--
Background fault noted
Non-USA vehicles only, continue to next test step.
--
-- Transmission is in electrical limp-home-mode Fault in software: 21/96 status Replace ETC
Transmission is in electrical limp-home-mode ETC control module (N15/3)
Traction system control module (N47)
Replace N15/3 only if no DTCs arestored
in N47
Transmission is in mechanical-hydraulic limp-home-mode ATF oil level
Piston B2/B3: piston guide
Harness
If the fault reappears after the test drive, and after all causes have been eliminated, then contact the regional office for help.
See 13/23 as well,
Check ATF fliud level, fill up as necessary,
see document AF27.00-P-0101A,
Remove, install brake B2, brake B3 and parking lock wheel,
see document AR27.50-P-0781A
Gear implausible, transmission slips, transmission is in mechanical-hydraulic limp-home-mode ATF oil level
ATF oil filter
Version coding
Rear axle ratio
Modulating pressure regulating solenoid
valve (Y3/6y1)
Command or Regulating, Shift Control Valves
Clutch K3
Free-wheeling units F1/F2
Circlips
Plain bushing at input/outpshaft worn out
Actuator motor at transfer case (Model 163)
See 13/24 as well,
Check ATF fliud level, fill up as necessary,
see document AF27.00-P-0101A
-- Unwanted actuation of torque converter lock-up function
 
Advise regional office
Torque converter lock-up does not function or requires to much power
 
Advise regional office
Selected gear not attained, transmission is in electrical limp-home-mode ATF oil level
Harness
ATF oil filter not installed
Shift pressure regulating solenoid
valve (Y3/6y2)
Command or Regulating, Shift Control Valves
See 13/27 as well,
Check ATF fliud level, fill up as necessary,
see document AF27.00-P-0101A
-- Fault in ETC control module (N15/3), however not critical for function of transmission. ETC control module (N15/3)

With DTC erase DTC and replace ETC control module only if the fault can be reproduced during a test drive.
Replace ETC





Transmission is in electrical limp-home-mode Connector connection between ETC control module and transmission is loose or has no electrical contact.

Harness is damaged, has abrasion damage, or is short circuited.

Solenoid valve(s) has bent contact finger.

Solenoid valve faulty.

Short circuit on the electrical conductor plate of the electro-hydraulic control unit due to deposited metal shavings


Applies up to transmission number 393328, thereafter the electrical conductor plate has been modified.

Endstage fault in ETC control module.
Check and verify proper electrical connection.



Test harness for short circuits to ground (-).

Re-bend contact finger for proper contact.

Replace solenoid valve.



Remove metal shavings.






Replace ETC control module.


Transmission is in electrical limp-home-mode, or does not transmit engine power. Connector connection between ETC control module and transmission is loose or has no electrical contact.

Harness is damaged, has abrasion damage, or is short circuited.

Short circuit on the electrical conductor plate of the electro-hydraulic control unit due to deposited metal shavings


Applies up to transmission number 393328, thereafter the electrical conductor plate has been modified.

RPM sensors are faulty.

Pressure plate below RPM sensors not installed.
Check and verify proper electrical connection.



Test harness for short circuits to ground (-).



Remove metal shavings.






Replace conductor plate.


Replace conductor plate.
-- Transmission gear selector lever in "Between Selections", transmission is in electrical limp-home-mode.
Applies to all models without "Touch Shift" feature.

Shift linkage improperly adjusted.

Transmission range recognition
switch (S16/10).


A fault code for the above is no longer set in memory as of software version e03/f08




Re-adjust shift linkage properly.

Replace the Transmission range recognition switch (S16/10), only if upon testing with the HHT, the HHT display shows "Between Selections" or "Fault".
Transmission is in mechanical-hydraulic limp-home-mode Torx screws (M8X60) loose or missing for piston guide on piston B2/B3

Harness is damaged, has abrasion damage, or is short circuited.
Tighten loose torx screws or replace missing torx screws.


Test harness for short circuits to ground (-).
Transmission is in mechanical-hydraulic limp-home-mode Wrong version code in ETC control module.


Wrong rear axle ratio.


ATF oil filter not installed.

Torx screws (M8X60) loose or missing for piston guide on piston B2/B3

Modulating pressure regulating solenoid
valve (Y3/6y1)


Applies up to transmission number 538312 only, thereafter screen installed in oil passage.

Command or Regulating, Shift Control Valves stuck due to foreign matter.
Check/Re-program ETC control module using HHT.

Check rear axle ratio, replace rear drive with proper rear axle for model

Install ATF oil filter.

Tighten loose torx screws or replace missing torx screws.

Replace Y3/6y1







Check valves for full travel and ease of movement, if necessary free up valves as needed.

Continued from 13/24 Clutch plates of clutch K3 are either burnt, have hot-spots or are worn down.












Free-wheeling unit (F1) faulty


Since it is possible that the free-wheeling unit F2 will be damaged as well, replace F2 (P/N 140 270 05 31) the hollow shaft, rear sun gear/clutch K3 as well.

Free-wheeling unit (F2) faulty
Replace inner and outer clutch plates of clutch K3.


Applies up to transmission number 331159 only, thereafter the thickness of the clutch plates changed.
Additionally replace torque converter lock-up clutch control valve (22).


Applies up to transmission number 221668 only.

Replace Free-wheeling unit (F1)







Replace F2 (P/N 140 270 05 31) the hollow shaft, rear sun gear/clutch K3.

Continued from 13/25 Circlip for outputshaft ball bearing is missing




Circlip for outer disc spring for Brake B3 is missing.



Circlip for disc spring for piston B2/B3 is not installed in groove.



Plain bushing at input/outpshaft worn out


Applies up to transmission number 1324240, exchange transmissions up to 346607. Thereafter plain bearing replaced with needle bearing

Actuator motor at transfer case (Model 163)
Replace transmission, flush transmission oil cooler and all lines. Replace torque converter only if upon flushing there are metal shavings present.

Replace transmission, flush transmission oil cooler and all lines. Replace torque converter only if upon flushing there are metal shavings present.

Replace transmission, flush transmission oil cooler and all lines. Replace torque converter only if upon flushing there are metal shavings present.

Swap inputshaft/outputshaft







Replace actuator motor.

Selected gear not attained, transmission is in electrical limp-home-mode. ATF oil filter not installed.

Harness is damaged, has abrasion damage, or is short circuited.

Shift pressure regulating solenoid
valve (Y3/6y2) stuck due to foreign matter.

Command or Regulating, Shift Control Valves stuck due to foreign matter.



Spring for regulating valve pressure control valve


Up to transmission number 6341191097
Install ATF oil filter


Test harness for short circuits to ground (-).


Replace (Y3/6y2).

Check valves for full travel and ease of movement, if necessary free up valves as needed.



Replace spring with P/N 140 993 58 01
1) Observe Preparation for Test, see 22.