Little help Please - AW4 TC No Lockup

[Hawkeye-Harris]

1989 XJ AW4.

I replaced a bad TPS with a Duralast brand (Autozone). Now the AW4 won't shift into TC lockup. So, I then re-placed the Duralast with the bad old one. Still no lockup. So put back the Duralast and left it. I adjusted it according to the RENIX manual.

Troubleshooting done: checked my solenoids for continuity, all good; checked fluid level, good; cleaned TCU connection. Planning a Drain and Re-fill tomorrow after I get some fluid and filter kit. Anyone care to recommend a type/brand?

The AW4 is shifting into all 4 gears, I can feel, see and hear the changes. But lockup is not working. Remember, this is a RENIX system so there is no codes, no CEL.

Grateful for any thoughts/ideas.

[Hawkeye-Harris]

Still no joy. Looking into re-replacing the TPS. Anyone have a favorite brand to look for? Advance Auto counter-man claims BWD brand that they sell is the exact part I would get if I bought one from the dealer. Can anyone comment on that, please? Amazon has that BWD for like 52USD.

[4.3LXJ]

On Jeep sensors, best to stick with Chrysler

[Hawkeye-Harris]

The torque converter still not locking up.
I did the following:
1. Changed tranny fluid and filter.
2. Replaced ground (negative) and positive battery cables with new 1GA cables with soldered on copper terminals. I wanted to upgrade the factory cables anyway as they appear to be something less than 4GA and were showing their age.
3. Added 4 new ground cables: engine-to-firewall, engine-to-right fender, battery-to-radiator support, transmission-to-body.
4. All ground surfaces were sanded down to bare metal for proper connection.
5. The infamous wire connection: 4-into-2, was soldered and re-taped (BTW it was in pristine condition, not even a hint of corrosion!).
6. All transmission connections/connectors and related sensor connections were separated, cleaned with electrical contact cleaner and re-connected.

Is there anything else I can do or check/test before I fork over more dough for another TPS?

[4.3LXJ]

I would recheck those solenoids before getting a TPS

[Hawkeye-Harris]

I would recheck those solenoids before getting a TPS

Rechecked them right at the solenoid when i had the pan off. TC solenoid had slightly less ohms than the other two; it was 9.8 and the others were 11.2. I would have tested them with battery voltage but was not for-sure-&-for-certain they operated directly on 12v and could not find anything that told me yes or no.

[4.3LXJ]

I believe the solenoids do. It is the computer sensors and associated parts of the cpu that operate on 5V

[Hawkeye-Harris]

Well too late now, I'm not removing the pan again w/o due cause. I suppose I could try tripping it from the C14 wire at the TCU?

[4.3LXJ]

First I would check to see you have a good circuit with the ohm meter. Then try tripping it

[Hawkeye-Harris]

First I would check to see you have a good circuit with the ohm meter. Then try tripping it

You mean checking C14 wire out of the TCU? Or ...?

[4.3LXJ]

I would check the solenoid resistance with the wire out of the TCU. Eliminates bad connections

[Hawkeye-Harris]

I would check the solenoid resistance with the wire out of the TCU. Eliminates bad connections

Using the cig lighter socket wall as my ground I tested these solenoid wires from the TCU connector:
C14: 13.2 ohms
C15: 12.9 ohms
C16: 12.9 ohms

[4.3LXJ]

That leaves you with two options I think. One is the TPS and the other is the TCU

[Hawkeye-Harris]

If I go hunting a tranny control unit, what years am I looking for? Again, this one is an '89, 6 banger.
Oh, I forgot: the previous own said the guy he bought it from put a '92 engine/tranny/x-fer case in it.