F. Modified Evaporator Temperature Sensor
1. Model 201
As of June 1987 production, a longer, modified temperature sensor with a smaller diameter probe was installed (A, Figure 9).
The modified probe is encased in metal to protect the sensor (NTC) against moisture. The previous version sensor was encased in plastic, except for the metal tip (B, Figure 9).
Note:
On the previous version temperature sensor, intruding moisture through the plastic body could lead to a short circuit in the sensor. This would result in keeping the compressor on continuously. The evaporator will ice-up and the cooling capacity, as well as the air flow, will be reduced.
The modified temperature sensor is interchangeable with the previous version. Due to the smaller diameter (1.0 mm smaller) of the modified temperature sensor, the following should be observed during installation:
Procedure
1.1 Remove evaporator temperature sensor (see Service Microfiche Air Conditioning System I, Model 201, job no. 83-543).
1.2 Remove temperature sensor mounting bracket from evaporator housing (2, Figure 10).
Locate the existing pathway for the sensor (between the fins).
1.3 With a small screwdriver, carefully bend the fin adjacent to the existing sensor pathway, (to create a new pathway for the new sensor, (Figure 11).
Note:
Removal of the evaporator housing cover (1, Figure 10) is not necessary in order to perform step 3.
1.4 Slide mounting bracket over temperature sensor. Guide temperature sensor through housing into the newly created pathway between the fins. Attach bracket to evaporator housing. Secure sensor to bracket and reconnect plug to harness.
2. Mode1 124 and 126
A modified evaporator temperature sensor has been installed on model 124 and 126 vehicles since the beginning of February 1988 production (Figure 12). In case of customer complaints regarding the evaporator icing-up (reduced cooling capacity with reduced air flow), install a modified temperature sensor with black NTC capsule (arrow, Figure 12; previous version had white capsule).