ENGINE DIAGNOSIS (RHZ ENGINE WITH SINGLE-CONNECTOR ECM)
6-73
TROUBLESHOOTING
STEP
ACTION
YES
NO
1
Was “ENGINE DIAG. FLOW TABLE” performed?
Go to Step 2.
Go to “ENGINE
DIAG. FLOW
TABLE”.
2
Does speedometer indicate vehicle speed?
Faulty “BLU / YEL”
wire or poor C51-19
connection.
If wire and connec-
tion are OK, intermit-
tent trouble or faulty
ECM.
Check for intermittent
referring to “Intermit-
tent and Poor Con-
nection” in Section
0A.
Go to Step 3.
3
VSS Power Supply Voltage Check:
1) With ignition switch OFF, remove VSS coupler.
2) With ignition switch ON leaving engine OFF, check
voltage between “BLK / WHT” wire terminal and
“BLK” wire terminal of VSS coupler.
Is voltage 10 – 14 V?
Go to Step 4.
“BLK / WHT” or “BLK”
wire open / short.
4
VSS Signal Harness Check:
1) With ignition switch ON leaving engine OFF, check
voltage between “BLU / YEL” wire terminal and
“BLK” wire terminal of VSS coupler.
Is voltage 4 V or more?
Go to Step 5.
Go to Step 6.
5
VSS Visual Inspection:
1) Remove VSS referring to “TRANSFER” section.
2) Check VSS drive and driven gears for damage and
excessive wear.
Are they in good condition?
Poor VSS connection
or VSS malfunction.
If connection is OK,
substitute a known-
good VSS and
recheck.
Replace VSS.
6
Speedometer Circuit Check:
1) With ignition switch OFF, disconnect G11 coupler
from combination meter.
2) With ignition switch ON leaving engine OFF, check
voltage between “BLU / YEL” wire terminal and
“BLK” wire terminal of VSS coupler.
Is voltage 4 V or more?
Substitute a known-
good combination
meter and recheck.
“BLU / YEL” wire
open / short or faulty
ECM.
If wire and connec-
tion are OK, substi-
tute a known-good
ECM and recheck.
