Hi all,
I have been researching the Klima relay and my options for how to deal with it. When I pulled the cap from my klima relay, I saw this:
OK, fine, I know I have an older engine in there, and I just fixed the tach for it today. But, because I "fixed" the tach to an older style setup, my EGR brain is not going to respond correctly, and I will have an issue with the Klima Relay anyway.
Ive obtained the most info from here:
KLIMA Basics missing from this forum
But still am not sure about my setup. So I have some questions and then some options for the sourse of action.
Since Linking 87 and KL sends the PBU compressor signal to the compressor bypassing all Klima interrupts, and since apparently the refrigerant low pressure switch in an 85 is between the Klima and the compressor, it seems that if I jumper over the klima by sticking a fused wires between the right holes, then all should be well. Right?
I am worried that if I jumper the Klima, that the AC will not cycle correctly. Is this a real fear, or should the "logic" that determines the cycling of the compressor be based on some other set of switches that is irrelevant to the Klima? Does anyone know if the 85 cars used a different ac compressor from earlier cars? Depending upon the connectivity via the Klima relay, it may not matter anyway. It seems that all 300D card used an R-4 compressor and that there is no real difference.
So, options... Of course my first option is to jumper past the Klima relay and hope for the best... However, I have to wonder about these unknown connections found under the hood:
And if they have anything to do with the AC and Klima.
Now, if I just jumper it over, per my research, the only things that Ill loose are as follows: the capability of more power when the kickdown switch closes (pedal on the floor); the capability of the relay to shut the a/c compressor down if the engine gets too hot.
Neither of these are earth shattering... but of course this means that jumpering the Kima relay must work to make the AC system operate as it did in 84 and earlier cars. Is this a safe bet?
Now, option #2. Say I obtained a new or good used Klima relay. Could I modify it such that of the three functions it protects for, i.e. 1) Signal from the CCU going through the Evap. temp switch and the low pressure cutout switch. This signal tells the Klima to close. 2) Signal from the kickdown switch. This signal tells the Klima to open. 3) Signal from a temperature switch. This signal tells the Klima to open if the temperature it above the setpoint. 4) Signal from the tach.
Could I somehow modify the klima such that the tach signal (not present) is always set in the relay to be correct and so the AC can operate? This way, assuming that all the rest of the wring is intact, I still get the low pressure protection and the kickdown shutoff conveneince.
Is this possible?
Finally, option #3: assume that all the connectivity to the Klima other than the tach signal is still in tact. Also assume that it is not smart/possible to modify a working klima to operate the rest of its logic without the tach signal. Could I then buy a different relay, use the pins from the klima setup, and have the relay operate such that if the CCU calls for cold air, it closes unless only two options, kickdown switch or temperature signal? That is, use a relay with one less option to cause it to open. I assume that with a single different relay (not necessarily drop into the existing holes) or a set of simpler relays wired up some way, I could gain this functionality.
Do I have basis, or am I just spewng out ideas that will never work. Any ideas or comments? I am fine with doing whatever, so long as I gain working AC. I just worry about the fact that I have a replacement engine, and its effects on the operation of the Klima functions, the EGR computer's effect on the AC and Klima setup, etc.
Any ideas or suggestions would be most appreciated.
Thanks!
JMH