O-Gauge Steamer
NAXJA Forum User
- Location
- Colorado Springs, Colorado
The Story...
I pulled parts from the JY (off a 98) for my 98. Pulled everything, switches, clockspring, servo and the PCM (just in case...).
Installed the parts and here is what I have.
1. Continuity from the PCM to the Servo. Validates the entire wiring...
2. When armed, the CC light comes on.
3. No CC action.
What I know.
1. Per the FSM, I looked for voltage at the servo with the engine running and the CC armed. Zero volts present.
2. I removed the brake light switch from the vehicle and probed the connection from the PCM with my Fluke 87. With the switch in the "brake applied" position, a solid 13.5 VDC is present at the input side of the normally closed switch. When the switch is put into the "normal" position, the voltage drops to zero. The dash light remains lit. In order to get the voltage back, the PCM has to be reset, i.e. turn off the engine and restart.
The voltage checks at the switch was with the servo disconnected per the FSM.
3. Replaced the PCM with the donor (later version) with no change, put the original back in.
4. According to my FSM, you need a minimun of 10" Hg for operation, I have 16.5 at idle, near 18 when the engine is at speed.
5. Tested the servo by jumping the solenoid connections to the battery. All three solenoids work just fine as does the servo when driven this way.
Short of getting a Megar to check for high impeadance shorts to ground, anyone have any ideas? At this point I'll even take a bad one...
Good thing I don't have much hair left or I would be pulling it out...
I pulled parts from the JY (off a 98) for my 98. Pulled everything, switches, clockspring, servo and the PCM (just in case...).
Installed the parts and here is what I have.
1. Continuity from the PCM to the Servo. Validates the entire wiring...
2. When armed, the CC light comes on.
3. No CC action.
What I know.
1. Per the FSM, I looked for voltage at the servo with the engine running and the CC armed. Zero volts present.
2. I removed the brake light switch from the vehicle and probed the connection from the PCM with my Fluke 87. With the switch in the "brake applied" position, a solid 13.5 VDC is present at the input side of the normally closed switch. When the switch is put into the "normal" position, the voltage drops to zero. The dash light remains lit. In order to get the voltage back, the PCM has to be reset, i.e. turn off the engine and restart.
The voltage checks at the switch was with the servo disconnected per the FSM.
3. Replaced the PCM with the donor (later version) with no change, put the original back in.
4. According to my FSM, you need a minimun of 10" Hg for operation, I have 16.5 at idle, near 18 when the engine is at speed.
5. Tested the servo by jumping the solenoid connections to the battery. All three solenoids work just fine as does the servo when driven this way.
Short of getting a Megar to check for high impeadance shorts to ground, anyone have any ideas? At this point I'll even take a bad one...
Good thing I don't have much hair left or I would be pulling it out...
