Code 21: Throttle Position (TP) Sensor Circuit (Non Scan)
1
•
•
IGNITION “OFF.”
DISCONNECT THROTTLE POSITION SENSOR
ELECTRICAL CONNECTOR.
IGNITION “ON.”
•
•
CONNECT A DVM FROM HARNESS TERMINAL “A”
(5
VOLT REFERENCE TO HARNESS TERMINAL “B”
SENSOR GROUND).
IS VOLTAGE READING OVER 4 VOLTS?
YES
NO
3
4
2
•
CONNECT DVM FROM HARNESS TERMINAL “A”
(CKT 416) TO HARNESS TERMINAL “C” (THROTTLE
POSITION SENSOR SIGNAL, CKT 417).
•
CONNECT DVM FROM THROTTLE POSITION
SENSOR HARNESS TERMINAL “A” TO A GOOD
GROUND ON ENGINE.
IS VOLTAGE READING OVER 4 VOLTS?
IS VOLTAGE OVER 4 VOLTS?
YES
NO
NO
YES
•
•
IGNITION “OFF.”
•
FAULTY CONNECTION
AT ECM
OR
CKT 416 OPEN
OR
SHORTED TO GROUND
OR
FAULTY CONNECTION
AT ECM
OR CKT 813 OPEN
OR
FAULTY ECM.
CONNECT DVM
CONNECT A TEST LIGHT
TO B+ BATTERY POSITIVE.
TOUCH TEST LIGHT TO
HARNESS TERMINAL “C”
BETWEEN HARNESS
TERMINAL “C” AND
ENGINE GROUND.
IS VOLTAGE OVER 4
VOLTS?
•
(THROTTLE POSITION
SENSOR SIGNAL).
IS TEST LIGHT “ON”?
FAULTY ECM.
YES
NO
CKT 417 SHORTED
TO VOLTAGE.
OPEN CKT 417
OR
FAULTY CONNECTION
AT ECM
OR
FAULTY ECM.
YES
NO
•
•
DISCONNECT ECM.
TOUCH TEST LIGHT
CONNECTED TO B+ (BAT
TERY POSITIVE) TO
THROTTLE POSITION
SENSOR FAULTY.
HARNESS TERMINAL “C”.
IS TEST LIGHT “ON”?
YES
NO
CKT 417 SHORTED
TO GROUND.
FAULTY ECM.
Index
90-823224--2 796
ELECTRONIC FUEL INJECTION (MULTI-PORT AND THROTTLE BODY) - 5C-89
| Categories | Mercury MerCruiser Manuals |
|---|---|
| Tags | Mercury MerCruiser 454 CID, Mercury MerCruiser 502 CID |
| Model Year | 1993, 1994, 1995, 1996, 1997 |
| Download File |
|
| Document File Type | |
| Copyright | Attribution Non-commercial |
(4 votes, average: 4.5 out of 5)
Marine readers have rated 1993 1997 Mercury-MerCruiser GM V8 454 CID 7.4L and 502 CID 8.2L Marine Engines Service Manual Number 16 4.5 out of 5.0 based on 4 product reviews. Hugely helpful service manual! Perfect. Thank you!
Manuals are all Important for Technician
This book is invaluable if you do your own repairs. Great book.
Could not find a copy until a search brought me here.
Excellent print.
Thank you