Honda Civic Service Manual page 920

Electrical Troubleshooting ('96 - 98 Modelsl
Troubleshooting Flowchart - Throttle position (Tpl Sensor
Possible Cause
. Disconnected throftle position
(TPl 3ensor connoctol
. Short or open in TP sensor wire
. Fauhy TP sensol
TCM CONNECTORS
Wire s;de of female terminals
. OBO ll Scan Tool indic.tes Code
P1790.
. Self-diagnosis E indicator light
blinks three times.
Check lor Anothar Code or MIL
Blinking:
1. Turn the ignition switch ON 1 ).
2. Check whether the OBD ll scan
tool indicates another code or
the Malfunction Indicator Lamp
(MlL) blinks (see secrion 11).
Does the OBD ll scan tool indicate
anothercode oristhe MIL blink-
ing?
Repair the PGM-FI systom (3ee
section 111.
Measure VREF Voltage:
1. Turn the ignition switch OFF.
2. Disconnect the A (26P) and B
{ 2 2 P } c o n n e c t o r s l r o m t h e
TCM.
3. Turn the ignition switch ON
{fl).
4. Measure the voltage bet\iveen
the 820 and A13 or 426 termi-
n a l s ,
Repair open or short in thc wire
b,stween the Bao tcrminal rnd the
ECM.
ls lhere approx. 5 V?
Measure TPS Voltago:
Measure the voltage between the
B4 and A13 or 426 terminals.
Repail open in the wire tr€tweon
the Erl t6.minal ind the TP sen3o..
ls there 0.4 - 0.6 V?
Check for loose TCM connectors.
lf necessary, substitute a known-
good TCM and r6check.
NOTE: Record all freeze data before you troubleshoot.
BLK
WHT/RED
A {26P1