Diagnostics For DTC P1808 - keywords auto auto-stop autostop auto-start autostart aux auxilary BAS code DTC ecm engine hybrid inop inoperative LAT light MIL no P1808 pump SES start stop switch tfp
| Subject: | Diagnostics for DTC P1808 - keywords auto auto-stop autostop auto-start autostart aux auxiliary BAS code DTC ecm engine hybrid inop inoperative LAT light MIL No P1808 pump SES start stop switch tfp |
| Models: | 2008 Chevrolet Malibu Hybrid |
| 2007-2008 Saturn Vue Greenline Hybrid |
| 2007-2008 Saturn Aura Greenline Hybrid |
| with 2.4L Engine (VIN 5 or Z - RPO LAT) |
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
The vehicle may have a concern of a DTC P1808. The following diagnostics may help find the cause.
Recommendation/Instructions:
For the DTC P1808 to set the ECM determines that the TFP signal A circuit has a concern. This is circuit 1224 from the C3 ECM connector terminal 2 to the N terminal at the C100 (20 way transmission) connector and then to the TFP switch in the transmission. (eSI Document ID#1816900)
The state of this circuit can be monitored by the PNP switch reading in the ECM Data List and then select the Hybrid Data List.
Check the circuit and then the TFP switch for being grounded or open at all times.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
