90 XJ AT shifting / TPS problem
#21
Guest
Posts: n/a
Re: 90 XJ AT shifting / TPS problem
Hello, yes I adjusted it, it won't adjust near far enough to get a
proper reading. The readings from the AT plug are .35v at idle and .01v
wide open. The readings while opening throttle are smooth. The ground
reading of .8v has me thinking I should splice a ground to the circuit,
this was recommended in another post. I did check chassis to block
grounds and I did the old jumper cable check with no change in reading.
Thanks, JK
proper reading. The readings from the AT plug are .35v at idle and .01v
wide open. The readings while opening throttle are smooth. The ground
reading of .8v has me thinking I should splice a ground to the circuit,
this was recommended in another post. I did check chassis to block
grounds and I did the old jumper cable check with no change in reading.
Thanks, JK
#22
Guest
Posts: n/a
Re: 90 XJ AT shifting / TPS problem
Hello, yes I adjusted it, it won't adjust near far enough to get a
proper reading. The readings from the AT plug are .35v at idle and .01v
wide open. The readings while opening throttle are smooth. The ground
reading of .8v has me thinking I should splice a ground to the circuit,
this was recommended in another post. I did check chassis to block
grounds and I did the old jumper cable check with no change in reading.
Thanks, JK
proper reading. The readings from the AT plug are .35v at idle and .01v
wide open. The readings while opening throttle are smooth. The ground
reading of .8v has me thinking I should splice a ground to the circuit,
this was recommended in another post. I did check chassis to block
grounds and I did the old jumper cable check with no change in reading.
Thanks, JK
#26
Guest
Posts: n/a
Re: 90 XJ AT shifting / TPS problem
I pulled the fuse from the TCU and it shifts fine manually, also took
some readings at the TCU and they are way off. I guess a bad TCU? The
link that Bill gave has some great info on checking the TCU but I was
looking at it backwards and thought it was 180 out. The guy also says
at the end that if the readings are within spec the TCU is a
transmission condemed unit, I'm thinking he meant out of spec.
some readings at the TCU and they are way off. I guess a bad TCU? The
link that Bill gave has some great info on checking the TCU but I was
looking at it backwards and thought it was 180 out. The guy also says
at the end that if the readings are within spec the TCU is a
transmission condemed unit, I'm thinking he meant out of spec.
#27
Guest
Posts: n/a
Re: 90 XJ AT shifting / TPS problem
I pulled the fuse from the TCU and it shifts fine manually, also took
some readings at the TCU and they are way off. I guess a bad TCU? The
link that Bill gave has some great info on checking the TCU but I was
looking at it backwards and thought it was 180 out. The guy also says
at the end that if the readings are within spec the TCU is a
transmission condemed unit, I'm thinking he meant out of spec.
some readings at the TCU and they are way off. I guess a bad TCU? The
link that Bill gave has some great info on checking the TCU but I was
looking at it backwards and thought it was 180 out. The guy also says
at the end that if the readings are within spec the TCU is a
transmission condemed unit, I'm thinking he meant out of spec.
#28
Guest
Posts: n/a
Re: 90 XJ AT shifting / TPS problem
I pulled the fuse from the TCU and it shifts fine manually, also took
some readings at the TCU and they are way off. I guess a bad TCU? The
link that Bill gave has some great info on checking the TCU but I was
looking at it backwards and thought it was 180 out. The guy also says
at the end that if the readings are within spec the TCU is a
transmission condemed unit, I'm thinking he meant out of spec.
some readings at the TCU and they are way off. I guess a bad TCU? The
link that Bill gave has some great info on checking the TCU but I was
looking at it backwards and thought it was 180 out. The guy also says
at the end that if the readings are within spec the TCU is a
transmission condemed unit, I'm thinking he meant out of spec.
#29
Guest
Posts: n/a
Re: 90 XJ AT shifting / TPS problem
JRK58@MSN.COM wrote:
>
> I pulled the fuse from the TCU and it shifts fine manually, also took
> some readings at the TCU and they are way off. I guess a bad TCU? The
> link that Bill gave has some great info on checking the TCU but I was
> looking at it backwards and thought it was 180 out. The guy also says
> at the end that if the readings are within spec the TCU is a
> transmission condemed unit, I'm thinking he meant out of spec.
Or he was meaning if it checked out ok, the tranny was condemned?
Do you have a transmitter on board by any chance? I know that a
transmitter can cause the TCU to have total brain farts if the wiring or
antenna are anywhere near it or it's harness.
On the 90, the ground still jumps out screaming at me....
I think I would run a dedicated ground jumper to the TCU just to see
what happens, same for your ground jumper idea on the TPS ground.
A lot of the computer grounds terminate on a bolt on or near the oil
dipstick. There will be a bunch of small black wires bolted on there.
That might be worth a clean too.
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)
>
> I pulled the fuse from the TCU and it shifts fine manually, also took
> some readings at the TCU and they are way off. I guess a bad TCU? The
> link that Bill gave has some great info on checking the TCU but I was
> looking at it backwards and thought it was 180 out. The guy also says
> at the end that if the readings are within spec the TCU is a
> transmission condemed unit, I'm thinking he meant out of spec.
Or he was meaning if it checked out ok, the tranny was condemned?
Do you have a transmitter on board by any chance? I know that a
transmitter can cause the TCU to have total brain farts if the wiring or
antenna are anywhere near it or it's harness.
On the 90, the ground still jumps out screaming at me....
I think I would run a dedicated ground jumper to the TCU just to see
what happens, same for your ground jumper idea on the TPS ground.
A lot of the computer grounds terminate on a bolt on or near the oil
dipstick. There will be a bunch of small black wires bolted on there.
That might be worth a clean too.
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)
#30
Guest
Posts: n/a
Re: 90 XJ AT shifting / TPS problem
JRK58@MSN.COM wrote:
>
> I pulled the fuse from the TCU and it shifts fine manually, also took
> some readings at the TCU and they are way off. I guess a bad TCU? The
> link that Bill gave has some great info on checking the TCU but I was
> looking at it backwards and thought it was 180 out. The guy also says
> at the end that if the readings are within spec the TCU is a
> transmission condemed unit, I'm thinking he meant out of spec.
Or he was meaning if it checked out ok, the tranny was condemned?
Do you have a transmitter on board by any chance? I know that a
transmitter can cause the TCU to have total brain farts if the wiring or
antenna are anywhere near it or it's harness.
On the 90, the ground still jumps out screaming at me....
I think I would run a dedicated ground jumper to the TCU just to see
what happens, same for your ground jumper idea on the TPS ground.
A lot of the computer grounds terminate on a bolt on or near the oil
dipstick. There will be a bunch of small black wires bolted on there.
That might be worth a clean too.
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)
>
> I pulled the fuse from the TCU and it shifts fine manually, also took
> some readings at the TCU and they are way off. I guess a bad TCU? The
> link that Bill gave has some great info on checking the TCU but I was
> looking at it backwards and thought it was 180 out. The guy also says
> at the end that if the readings are within spec the TCU is a
> transmission condemed unit, I'm thinking he meant out of spec.
Or he was meaning if it checked out ok, the tranny was condemned?
Do you have a transmitter on board by any chance? I know that a
transmitter can cause the TCU to have total brain farts if the wiring or
antenna are anywhere near it or it's harness.
On the 90, the ground still jumps out screaming at me....
I think I would run a dedicated ground jumper to the TCU just to see
what happens, same for your ground jumper idea on the TPS ground.
A lot of the computer grounds terminate on a bolt on or near the oil
dipstick. There will be a bunch of small black wires bolted on there.
That might be worth a clean too.
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)