STEP/SEQUENCE
RESULT
WHAT TO DO NEXT
TM 9-2320-363-20-1
Section 4
TROUBLESHOOTING CHARTS
E.
FLASH CODE:
21
J1587 CODE:
P91 3. ELECTRONIC FOOT PEDAL ASM (EFPA) CIRCUIT FAILED HIGH
(VOLTAGE HIGH) ALSO CALLED THROTTLE POSITION SENSOR (TPS)
NOTE -
This chart is only to be used if:
1)
All basic mechanical checks and physical inspections have been performed with no problem found, and
2)
Diagnosis of DDEC-III was started at step Start-1, pg 3-345.41 and you have now been referred here.
21-1
Multiple Code Check
Were there any other active
No other codes.
Go to 21-2.
codes besides 91/3?
active codes.
Yes, any or all
Go to VEH5V-1 (page 3-345.419)
of the following active
codes: 187/3, 91/4
Yes - But none,
Go to 21-2.
of the above.
21-2
Sensor Check
Turn ignition off.
Any code
Go to 21-3.
Disconnect TPS connector.
except Code 91/3).
Turn ignition.
Read active codes.
Code 91/3 (and any
Go to 21-7.
other codes).
21.3
Return Circuit
Check
Turn ignition off.
Less than or
Go to 21-4.
Install a jumper wire between pins
equal to 5 ohms.
A and B of the TPS harness
connector.
Greater than
Return line (ckt#952) and/or
Disconnect the vehicle harness
5 ohms open.
signal (ckt#417) is open. Repair
connector at the ECM.
open. Then go to 21-30.
Read resistance between sockets
D2 and C3 on the vehicle harness
connector.
21-4
Check TPS
Adjustment
Reconnect vehicle harness
Getting 48-144
Go to 21-6.
connector and plug TPS back in.
counts at no throttle and
Hook-up DDR to the DDL
832 & 968 counts at full
connector and select Throttle
throttle.
Sensor display.
Read Throttle Counts at both no
Not getting the above
Go to 21-5.
throttle and full throttle.
reading.
Change 3 3-345.231