Jeep Wrangler TJ. Manual - part 170
Symptom:
P1687-NO COMMUNICATION WITH THE MIC
When Monitored and Set Condition:
P1687-NO COMMUNICATION WITH THE MIC
When Monitored:
Continuously with engine running.
Set Condition:
The code sets in approximately 25 seconds if no BUS messages are
received from the MIC.
POSSIBLE CAUSES
OTHER BUS PROBLEMS PRESENT
INTERMITTENT WIRING AND CONNECTORS
MIC - NO COMMUNICATION
TRANSMISSION CONTROL MODULE
TEST
ACTION
APPLICABILITY
1
With the DRBIII
t, Check the STARTS SINCE SET counter for P1687.
Note: This counter only applies to the last DTC set.
Is the STARTS SINCE SET counter set at 0?
All
Yes
→ Go To 2
No
→ Go To 5
2
With the DRBIII
t, check all of the other modules on the vehicle for evidence of a
vehicle bus problem.
Bus related DTC’s in other modules point to an overall vehicle bus problem. Other
symptoms such as a customer complaint of intermittent operation of bus controlled
features also indicate a bus problem.
Does the PRNDL display indicate
9No Bus9 or is there any evidence of an overall
vehicle bus problem?
All
Yes
→ Refer to the Communications category and perform the appropri-
ate symptom.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER
1.
No
→ Go To 3
3
Ignition on, engine not running.
With the DRBIII
t, clear all DTC’s.
Start the engine in park.
With the DRBIII
t, read the MIC DTC’s.
Can the DRBIII
t communicate with the MIC?
All
Yes
→ Go To 4
No
→ Refer to the Communication category and perform the appropri-
ate symptom related to No Response to MIC.
Perform 42RLE TRANSMISSION VERIFICATION TEST - VER
1.
405
TRANSMISSION - 42RLE