Speedo Not Working/ O/D OFF Light Flashing - Could this be the reason? (1 Viewer)

[80SeriesNomads]

Hey everyone,

All of a sudden, the speedometer stopped working. Everything else works just fine. Occasionally, the O/D OFF light starts flashing. After turning the engine off and on again, the flashing stops.

I've checked fuses, earth cables, etc., pretty much followed the great advice in this forum.

Also, I checked the speed sensor and it looks fine to me. Then I followed the cable coming from the speed sensor and found that one of the three cables on the connector is loose.

Could this be the reason the speedometer isn't working and therefore the O/D OFF light flashes occasionally?

Thanks, guys.

 

[jonheld]

The 2 connectors on top of the transfer case are for switches that indicate low range and neutral. They have nothing to do with vehicle speed sensors.
What does the FSM for your truck tell you about a flashing OD lamp?

 

[80SeriesNomads]

The 2 connectors on top of the transfer case are for switches that indicate low range and neutral. They have nothing to do with vehicle speed sensors.
What does the FSM for your truck tell you about a flashing OD lamp?

Thanks mate,

FSM doesn't list a flashing O/D OFF light at all. Or at least, I couldn't find anything:



I'm going to check the 2nd speed sensor this weekend.

 

[Crossthreaded]

Did you disassemble the speed sensor when you checked the pin? I had a speed sensor fail recently due to the speedo oil seal giving out. The VSS was full of gunk and seized. Once cleaned and with a new oil seal it's been working fine.

 

[80SeriesNomads]

Did you disassemble the speed sensor when you checked the pin? I had a speed sensor fail recently due to the speedo oil seal giving out. The VSS was full of gunk and seized. Once cleaned and with a new oil seal it's been working fine.

I just took the little pin out and everything looked fine. But if you're referring to the drive gear, I haven't touched it yet.

 

[BILT4ME]

Hey everyone,

All of a sudden, the speedometer stopped working. Everything else works just fine. Occasionally, the O/D OFF light starts flashing. After turning the engine off and on again, the flashing stops.

I've checked fuses, earth cables, etc., pretty much followed the great advice in this forum.

Also, I checked the speed sensor and it looks fine to me. Then I followed the cable coming from the speed sensor and found that one of the three cables on the connector is loose.

Could this be the reason the speedometer isn't working and therefore the O/D OFF light flashes occasionally?

Thanks, guys.

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View attachment 3586536

What year is your truck?

I found another thread on here referencing the OD Off Light Flashing.

1994 FZJ80 Overdrive flickers

So when I drive the overdrive light turns on and off regularly but not always. It rather seems like a timed flash than flickering. If I turn on overdrive it works. The light does not affect anything other than being annoying. Any ideas?

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