Like so many before me, my center diff is not locking. I have a 1991 FJ80 with Factory CDL dash Switch.
Ok, so I’ve been trying to figure out what I am missing here. Here is everything I’ve done to try and diagnose the issue. I have gone through the PNWadventures write up, I’ve seen the Toysrus instructions, I have copies of the troubleshooting pages digitally downloaded.
- Jacked up front passenger, wheel in air still spins when 4lo or CDL dash switch engaged.
- did circles on gravel roads in 4lo and/or CDL dash switch engaged, no change
- checked 10amp gauge fuse. Good
-checked 30amp diff fuse. Good
- jumped the CDL indicator switch, CDL light in dash lights up. Still replaced the indicator switch anyways.
- replaced the 4lo indicator switch.
- no cdl dash light when in 4lo or when 4lo indicator harness is jumped.
- continuity test on transmission relay checks out fine.
- 9V test on transmission relay, checks out fine
- relay clicks when shifted into 4lo. No click when CDL button is pressed.
- no noise from actuator when shifted into 4lo or CDL dash button pressed.
- no noise from actuator when 4lo indicator harness is jumped.
-replaced the CDL dash switch, and still no relay click.
- replaced the transmission relay, same results as the original relay.
Now I am here posting for help. I’m pretty sure my actuator isn’t functioning. The only test I haven’t done is apply 9V to the actuator.
My questions are:
What could be the reason my CDL dash switch is not activating the transmission relay?
How do I check that power is being sent from the dash switch to the transmission relay?
Will bad grounds in the actuator cause the CDL dash switch not to function?
Sorry to post a topic that has been well covered, but after reading all these different write ups I’m stumped.
Update:
Ok, so I’ve been trying to figure out what I am missing here. Here is everything I’ve done to try and diagnose the issue. I have gone through the PNWadventures write up, I’ve seen the Toysrus instructions, I have copies of the troubleshooting pages digitally downloaded.
- Jacked up front passenger, wheel in air still spins when 4lo or CDL dash switch engaged.
- did circles on gravel roads in 4lo and/or CDL dash switch engaged, no change
- checked 10amp gauge fuse. Good
-checked 30amp diff fuse. Good
- jumped the CDL indicator switch, CDL light in dash lights up. Still replaced the indicator switch anyways.
- replaced the 4lo indicator switch.
- no cdl dash light when in 4lo or when 4lo indicator harness is jumped.
- continuity test on transmission relay checks out fine.
- 9V test on transmission relay, checks out fine
- relay clicks when shifted into 4lo. No click when CDL button is pressed.
- no noise from actuator when shifted into 4lo or CDL dash button pressed.
- no noise from actuator when 4lo indicator harness is jumped.
-replaced the CDL dash switch, and still no relay click.
- replaced the transmission relay, same results as the original relay.
Now I am here posting for help. I’m pretty sure my actuator isn’t functioning. The only test I haven’t done is apply 9V to the actuator.
My questions are:
What could be the reason my CDL dash switch is not activating the transmission relay?
How do I check that power is being sent from the dash switch to the transmission relay?
Will bad grounds in the actuator cause the CDL dash switch not to function?
Sorry to post a topic that has been well covered, but after reading all these different write ups I’m stumped.
Update:
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