6 Automatic transmission
REF•10Fault Finding
Note:Due to the complexity of the automatic transmission and its
electronic control system, it is difficult for the home mechanic to
properly diagnose and service this unit. For problems other than the
following, the vehicle should be taken to a dealer service department
or automatic transmission specialist.
Fluid leakage
m mAutomatic transmission fluid is usually deep red in colour. Fluid
leaks should not be confused with engine oil, which can easily be
blown onto the transmission by airflow.
m mTo determine the source of a leak, first remove all built-up dirt and
grime from the transmission housing and surrounding areas, using
a degreasing agent, or by steam-cleaning. Drive the vehicle at low
speed, so airflow will not blow the leak far from its source. Raise
and support the vehicle, and determine where the leak is coming
from. The following are common areas of leakage:
(a) Housing joints (Chapters 1 and 7, Part B).
(b) Dipstick tube (Chapters 1 and 7, Part B).
(c) Transmission-to-fluid cooler pipes/unions (Chapters 3 and 7,
Part B).
(d) Speedometer drive pinion O-ring (Chapter 7, Part B).
(e) Differential side gear oil seals (Chapter 7, Part B).
Transmission fluid brown, or has burned smell
m mTransmission fluid level low, or fluid in need of renewal (Chapter 1).
Transmission will not downshift (kickdown) with
accelerator pedal fully depressed
m mLow transmission fluid level (Chapter 1).
m mIncorrect selector cable adjustment (Chapter 7, Part B).
m mEngine management system fault (Chapters 1, 4, 5 and 6).
General gear selection problems
m
mChapter 7, Part B, deals with checking and adjusting the selector
cable on automatic transmissions. The following are common
problems which may be caused by a poorly-adjusted cable:
(a) Engine starting in gears other than Park or Neutral.
(b) Indicator on gear selector lever pointing to a gear other than the
one actually being used.
(c) Vehicle moves when in Park or Neutral.
(d) Poor gear shift quality or erratic gear changes.
Refer to Chapter 7, Part B for the selector cable adjustment
procedure.
Engine will not start in any gear, or starts in gears
other than Park or Neutral
m mIncorrect selector lever position sensor adjustment (Chapter 7,
Part B).
m mIncorrect selector cable adjustment (Chapter 7, Part B).
Transmission slips, shifts roughly, is noisy, or has no
drive in forward or reverse gears
m mThere are many probable causes for the above problems, but the
home mechanic should be concerned with only one possibility -
fluid level. Before taking the vehicle to a dealer or transmission
specialist, check the fluid level and condition of the fluid as
described in Chapter 1. Correct the fluid level as necessary, or
change the fluid if needed. If the problem persists, professional
help will be necessary.
7 Driveshafts
Clicking or knocking noise on turns (at slow speed
on full-lock)
m mLack of constant velocity joint lubricant (Chapter 8).
m mWorn outer constant velocity joint (Chapter 8).
Vibration when accelerating or decelerating
m
mWorn inner constant velocity joint (Chapter 8).
m mBent or distorted driveshaft (Chapter 8).
8 Braking system
Note:Before assuming that a brake problem exists, make sure that the tyres are in good condition and correctly inflated, that the front wheel
alignment is correct, and that the vehicle is not loaded with weight in an unequal manner. Apart from checking the condition of all pipe and hose
connections, any faults occurring on the Anti-lock Braking System (ABS) should be referred to a Ford dealer for diagnosis - the same applies to the
components of the Traction Control System (TCS).
Vehicle pulls to one side under braking
m mWorn, defective, damaged or contaminated front or rear brake
pads/shoes on one side (Chapter 1).
m mSeized or partially-seized front or rear brake caliper/wheel cylinder
piston (Chapter 9).
m mA mixture of brake pad/shoe lining materials fitted between sides
(Chapter 1).
m mBrake caliper mounting bolts loose (Chapter 9).
m mRear brake backplate mounting bolts loose (Chapter 9).
m mWorn or damaged steering or suspension components (Chap-
ter 10).
Noise (grinding or high-pitched squeal) when brakes
applied
m mBrake pad or shoe friction lining material worn down to metal
backing (Chapter 1).
m mExcessive corrosion of brake disc or drum (may be apparent after
the vehicle has been standing for some time) (Chapter 1).
m mForeign object (stone chipping, etc) trapped between brake disc
and splash shield (Chapter 1).
Excessive brake pedal travel
m mInoperative rear brake self-adjust mechanism (Chapter 9).
m mFaulty master cylinder (Chapter 9).
m mAir in hydraulic system (Chapter 9).
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