1998 Chevy S-10 trans and or eletrical

DOORTEK

MEMBER
1998 CHEVROLET S-10
6 CYL
4WD
AUTOMATIC
102,446 MILES

I have a 2 part prob I feel may be related: 1) Trans slips in first from stop.
2) Drive indicator and gas gage goes blank intermittently (more often than not) when put in gear: then wont shife into 3rd however there is no trans slip when that happens.
Error codes are as follows:
P0740 torque conv. Clutch cirict open
P0785 Shift/timing solenoid
P1860 tcc pwm selonoid circit
P1870 ?

My thought was replacing the shift solenoid however due to a disabilty I am to short on cash for trial and error

1 Reply

BRIAN 1

MECHANIC
1,030 POSTS

Before you replace any parts follow this info, Some customers may comment on one or more of the following conditions:

"� The Malfunction Indicator Lamp (MIL) is ON.

"� The transmission is defaulted to second gear (4L80/85-E).

"� The transmission is defaulted to third gear (4L60/65-E).

"� The instrument cluster is inoperative.

Upon investigation, one or all of the diagnostic trouble codes (DTCs) P0740, P0753, P0758, P0785, P0787, P0973, P0976, P1860, P2761, P2764 and P2769 may be set depending on the vehicle.

Cause
The most likely cause of this condition may be a loss of voltage to the transmission solenoid power supply circuit.

This condition may also be the result of an incorrect installation of an aftermarket electronic device such as a remote starter or alarm system.

Correction
Important: If the vehicle is equipped with an aftermarket electronic device and the DTCs are being set when the device is being used, verify that the appropriate fuse is being supplied battery voltage during operation. If voltage is not present at this fuse, these DTCs will be set due to lack of voltage at the solenoids. This condition is most likely to occur with an incorrectly installed remote starting system. If this is the case, refer the customer to the installer of the system for corrections. ANY REPAIRS DUE TO AFTERMARKET INSTALLATION OF ACCESSORIES IS A NON-WARRANTABLE ITEM.

With the ignition switch in the RUN position, test for battery voltage at the circuit fuse in the transmission solenoid power supply circuit. If battery voltage is present at the fuse, inspect the ignition voltage circuit between the fuse and the transmission for possible opens.
If battery voltage is not present at the fuse, test for continuity between the fuse and the ignition switch. If NO continuity is between the fuse and the ignition switch, repair the open in that circuit.
If you have continuity between the fuse and the ignition switch, the most likely cause is the ignition switch. Replace the ignition switch using the appropriate Ignition Switch Replacement procedure. Start by checking fluid level and condition of fluid, see if its burnt. Check fuses also. Post back with any other questions and will advise.