Upshift lamp

A

Aquit45

NAXJA Forum User

Location

Oak Hills, Ca

• Apr 4, 2006

• #1

I have an auto 91 cherokee and im wondering how do they make the little light from not going on. Ive read that its controlled trough the engine computer, dose the computer know it an automatic or how dose this work?

 

B

bj-666

NAXJA Forum User

Location

Rhode Island

• Apr 4, 2006

• #2

they don't put one in on autos ????

 

R

Rick Anderson

NAXJA Forum User

Location

Lusby, MD

• Apr 4, 2006

• #3

Sounds like you vehicle may have originally came with a Standard Trans and someone converted it too an automatic. The automatic has a different PCM than the standard, which I imagine the automatic PCM wouldn't be programmed to light that light.

 

87manche

NAXJA Forum User

Location

Ohio

• Apr 4, 2006

• #4

If it was an auto from the factory there's probably not a bulb in the socket

 

5-90

NAXJA Forum User

Location

Hammerspace

• Apr 4, 2006

• #5

I made mine stop working (1988 XJ BA-10) by just pulling out the lamp. Damn thing's usually wrong anyhow.

5-90

 

S

sflier

NAXJA Forum User

Location

Danbury, CT

• Apr 5, 2006

• #6

Initially I couldn’t stand the idiot shift light. I mean, who are they to tell me when to shift? But, after so many funny comments from people who rode with me, I left it working as a bit of a novelty. I'm assuming the computer lights it based on input from engine RPM and manifold pressure? If so, I'll treat it as a "MAP sensor is working" idiot light.

 

Matthew Currie

NAXJA Member #760

Location

Vermont, land of big clay

• Apr 5, 2006

• #7

I may be wrong but I thought that 91-up models had a different engine computer for automatics than manuals, so maybe they actually left that function out.

 

I

iBran

NAXJA Forum User

Location

Minneapolis, MN

• Apr 5, 2006

• #8

I'm not 100% sure, but I'm almost positive that my '94 (automatic) doesn't have a bulb in that socket.

I'd assume that it's controlled by the ECU or TCU though, so even if you were to stick a bulb in there, it still wouldn't work.

 

B

bajacalal

NAXJA Forum User

Location

San Diego (North County), California

• Apr 5, 2006

• #9

The used gauge cluster I bought (to upgrade to full gauges) did not have bulbs installed for options that the jeep diddn't have. It diddn't have the upshift, airbag or 4WD lights. Is the light federally mandated? I've seen it on other vehicles. Just take it out, it will always have you lugging the engine in 5th at 35mph.