Part Time light/arrow

[ParadiseMJ]

I'm putting the wiring back together on my project truck. 88 MJ Pioneer 4.0 BA-10. I'm posting a few threads to get my way around this. When I get a bit more info I'll share what I get in a build thread.

 

When I start it up the "part-time" light comes on, but it's not in 4WD. Then it will go off, then on, off etc.

 

 

Just when I'm starting it, the "arrow" on the same light panel comes on, then goes off. Sitting in the driveway, if I rev the engine past 2K RPM the arrow comes on, then off. Did I say it's not in 4WD.

 

 

I've never seen the arrow on my 90 XJ. In 4WD or not. What does the arrow indicate?

[Gjeep]

It's an upshift light. Supposed to be the best time to shift for mpg.

[Dirteatr717]

Its suppose to pop up when you hit the right rpm to shift so u save gas :waving: I ignore it for a little and listen to my motor hmmmmmm :chillin:

[purplexj]

But why is it coming on if he's not driving. Mine only comes on while driving. Try pulling the dash and unplug replug that harness . Or if you have another cluster. I have a couple downstairs.

[Drahcir495]

But why is it coming on if he's not driving. Mine only comes on while driving.

I will try this one - I believe the light works of the RPM/Tach of the Truck. If his is anything like mine, it hits higher RPM's at start up and triggers the light to go off.

 

That almost sounds plausible ~ even if it was pulled from my back pocket :D

[ParadiseMJ]

All right. I get the arrow - since I have an AW4 in the XJ that would explain why I've never seen an arrow. In the 5 spd. - arrow as a "recommended" shift point. Seems like overkill, I'm pretty sure I know when to shift. I just may delete that bulb.

 

Soo, any ideas why the PT light is coming on and off when I do not have the TC in 4WD. The vac lines are all good (so far as I can tell) and tight with no air leakage. Could the CAD be sticking or stuck in locked/unlocked.

[purplexj]

My t/c has a pig tail coming off of it going to a harness running up to the firewall on the pass side. Maybe check those connections. If you shift when the arrow tells you to, you tend to do alot of lugging . Especially pulling a trailer up hill from a stop !

[Pete M]

I would shift the CAD over permanently, pull the vacuum hoses and PT bulb (and the shift bulb), and bask in the knowledge that I know more than my truck knows. :D

[purplexj]

Spoken like a true shade tree mechanic. No insult intended. I wold do the same thing except that I never connected my t/c lights. Plus i ignor the upshift arrow anyway. :cheers: