4HP22EH - don't know if it shifts properly...

[Rustam]

I'm not sure whether the transmission shifts correctly. I replaced the transmission about 2000 miles ago. Initially, in first, second and third gears the car provided an effect of backpressure - decelerated very quickly. I figured that the effect was due to absence of "break in" period. Well that period seems to have taken place for those gears - except 4th one. Shifting to 4th gear does not seem to occur - at the point of shifting, the car squats for half a second, but RPM's do not drop. The rear end gives whining sound and same effect of backpressure exists. The whining is absent in Sport mode. That tells me that the car does not shift from 3rd to 4th (can I possibly be mistaken here?)...

I checked the switches - sem and shifter switch, cleaned the shifter switch, the speedometer shows correct letters for gears and modes (as it did in fact). I know that previous owner had tampered with the wiring, at least at the point of SEM switch whereupon the contacts for Sport mode were connected for good.

Perhaps someone can help me - my questions are:

How can I check solenoids of the transmission?
How can I check that the transmission computer is correct? It seems impossible to search for this information through websites.

What else should I check besides consistency in wiring?

[Javier]

How can I check solenoids of the transmission?

Guess you have already the pin out of the transmission connector. If not, let me know.

Javier

[Rustam]

How can I check solenoids of the transmission?

Guess you have already the pin out of the transmission connector. If not, let me know.

Javier

Thank you for the pdf. I it looks like the solenoids 1 and 2 should work fine since switching is available for 1,2 and 3 gears. Confusing. Perhaps I should start by pulling out the harness for the test. Do you know of any source that can make available information regarding identification of transmission computer?

I don't have the pin-out of the connector.

Can you comment on having a few wires attached to the solenoid connectors in order to check currents while driving?

I really appreciate the help...

[Javier]

the solenoids for shorts or open circuits.

This is the connector pin out and the diagram, 1989 is not supposed to have solenoid Nbr. 4.

Javier

[Rustam]

the solenoids for shorts or open circuits.

This is the connector pin out and the diagram, 1989 is not supposed to have solenoid Nbr. 4.

Javier

I found the PDF in my mailbox. One thing strikes me very much - someone once told me to check the SEM switch, reasoning that it may be no good since the shift does not occur. The person particularly stressed that those switches were of different design, sometime around production date of my car. Parts vendors show consistently a photo of "SEM" switch for my application - just the one I have in my car. Now the PDF that you sent me shows "AM" switch, not "SEM". How much can I trust this PDF?

[Javier]

My german 1992 e34 does also have a SEM switch instead, and there are some slight differences.

Alternative is that yours is a 1988 model (6/88 trough 2/89).

I sent you 1988EGS drawing, it shows three position switches. But if your cluster shows transmission mode properly, switch should be OK.


Javier

[Javier]

I think I recall someone explaining that the gear is in sport mode up to the moment the car gets warm, may be Bill can confirm. If yours seem to be permanently in sport mode, may be it has to do with this, may be it is missing a signal from the ECU telling it is ready to go!!

Javier

[Rustam]

Alternative is that yours is a 1988 model (6/88 trough 2/89).

I sent you 1988EGS drawing, it shows three position switches. But if your cluster shows transmission mode properly, switch should be OK.

My car was made in 9/88. Now that I see that besides the difference in the switch application there is a diffrence in solenoid number I wonder whether I got correct transmission configuration. If the transmission is lacking one of the solenoids (does it or does it not? or is it simply the wiring missing the wire? what exactly does "not used" mean in the schematics?) I will have to explore the option of rewiring for "AM" switch. The schematics seem to show same transmission control unit for both cases. Do you know whether that is true?

DOES ANYONE KNOW WHETHER TRANSMISSION CONTROL UNIT IS SAME FOR 7 PIN AND 8 PIN TRANSMISSION CONNECTOR ON 4HP22EH???

If yours seem to be permanently in sport mode, may be it has to do with this, may be it is missing a signal from the ECU telling it is ready to go!!

Do you know which wire sends that signal??

My speedometer does not show it to be in sport mode constantly however - whether it may be possible to have sport mode without seing "S" on the speedometer is another thing of mystery to me since I don't know about the condition of the wiring. As far as showing correct letter per usage of the switch - yes it does do that.

[Javier]

extra solenoid, so both things are not necessarily tied together. Regarding the EGS control box, would suggest o check with the on line ETK for part number clarification.

Also check your transmission for the existence of the extra solenoid. May be it is there as your original one. (an ohm meter in the connection socket would do it).

Edit: Not absolutely sure about the cold operation in S mode for this gear, in any case, mine shows in the display what is selected in the switch. May be someone else can confirm.


Javier

[Rustam]

really appreciate it...

extra solenoid, so both things are not necessarily tied together. Regarding the EGS control box, would suggest o check with the on line ETK for part number clarification.

Also check your transmission for the existence of the extra solenoid. May be it is there as your original one. (an ohm meter in the connection socket would do it).

Edit: Not absolutely sure about the cold operation in S mode for this gear, in any case, mine shows in the display what is selected in the switch. May be someone else can confirm.


Javier