Toyota Celica 2005 Repair Manual page 29

IN−28
6. CIRCUIT INSPECTION
How to read and use each page is shown below.
D Diagnostic Trouble Code No. and Detection Item
DTC P0325
CIRCUIT DESCRIPTION
Knock sensor is fitted to the cylinder block to detect engine knocking. This sensor contains a piezoelectric element which
generates a voltage when it becomes deformed, which occurs when the cylinder block vibrates due to knocking. If engine
knocking occurs, ignition timing is retarded to suppress it.
DTC No. DTC Detecting Condition
No knock sensor 1 signal to ECM with engine speed,
P0325
1,200 rpm or more.
If the ECM detects the above diagnosis conditions, it operates the fall safe function in which the corrective retard angle
value is set to the maximum value.
WIRING DIAGRAM
Knock Sensor 1
2005 CELICA (RM1131U)
INTRODUCTION
Knock Sensor 1 Circuit Malfunction
D Open or short in knock sensor1 circuit
D Knock sensor 1 (looseness)
D ECM
ECM
12
GR
KNK
E6
E1
− HOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
D Circuit Description
The major role and operation, etc. of the circuit
and its component parts are explained.
Trouble Area
D Indicates the diagnostic trouble code, diagnostic
trouble code set parameter and suspect area of
the problem.
D
Wiring Diagram
This shows a wiring diagram of the circuit.
Use this diagram together with ELECTRICAL
WIRING DIAGRAM to thoroughly understand the
circuit.
Wire colors are indicated by an alphabetical code.
B = Black, L = Blue, R = Red, BR = Brown,
LG = Light Green, V = Violet, G = Green,
O = Orange, W = White, GR = Gray, P = Pink,
Y = Yellow, SB = Sky Blue
The first letter indicates the basic wire color and
the second letter indicates the color of the stripe.
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